text:
Did the Buddha speak Pali? Are the suttas his word verbatim?

Was Pali the language spoken during the time of the Buddha, and would he have spoken this language?
Are the suttas contained in the Pali Canon verbatim what the Buddha said, or would things have been changed due to centuries of oral transmission?

A related question is posted here[link]http://buddhism.stackexchange.com/questions/19340/are-there-any-proven-facts-to-support-that-pali-is-more-authentic-for-the-buddha[/link]

The short answer is no, and no. The Pāḷi Canon is a translation. Although people in Central Ganges Valley all spoke closely related dialects at the time we think the Buddha lived. The problem of having different words for things was noted at least once in a Pāli text. In MN iii.234 (Araṇavibhanga Sutta) that there can be many local words for the same object, e.g. pāti, patta, vittha, serāva, dhāropa, poṇa or pisīla (all variations on 'bowl'). The text says that to insist on one name would be to cause conflict, and in any case one knows the object whatever it is called.
Pāḷi is a kind of formal language which was no one's vernacular, but was probably widely understood. It is similar in some ways to two different dialects as represented by the Asoka inscriptions: one in the West of Indian (Girnar) and one in the East (Magadha). In some of the earlier parts of the Pāli Canon, such as the Suttanipāta, the dialects are quite mixed up and it is confusing trying to translate them. Later things settled down.
The first answer, by Buddho, is rather speculative about the Buddha's language. There is no basis for this speculation. It's a guess with no evidence one way or another. As I say we do not know what language the Buddha spoke. In fact we do not really know what his name was, so how could we know his language!?
Secondly the texts are very clearly the result of a long process of telling, retelling, and editing. This is most clear when one compares the Pāli texts with those in Gāndhārī and Chinese. The different Canons are organised differently and within suttas words, phrases and large chunks of text get moved around. Some texts have clearly been tampered with and other were clearly written much later than the rest.
It's entirely possible that some of it was said by the Buddha and translated into Pāli with little loss of meaning. But we'll never know how much and how faithfully.
But the texts are no less fascinating for this I find.

Source material for these claims?

For Pāḷi as a language see e.g. Jan Nattier. Church Language and Vernacular Language in Central Asian Buddhism. Numen. Vol. 37, Fasc. 2 (Dec., 1990), pp. 195-219
or K R Norman. A Philological Approach to Buddhism. - there are pirate copied online.
For the structure of the different Canons see The Pāḷi Canon, the Chinese Tripiṭaka, etc. Many recent articles by Bhikkhu Anālayo which can be found here: https://uni-hamburg.academia.edu/venerableanalayo

Thanks for the much better answer. Quite honestly all matters of history are murky, especially when it is 2600 years old. I didn't want to definitively say no to the questions, because even that isn't a certainty. It's only the considered intellectual opinion of historians, not a certain fact. At best the answer is, we don't know.

Hi Buddho. Yes, the answer is often "we don't know". With care we can often infer things about history. For example the Pāḷi canon mentions certain cities that we have good archaeological evidence for and thus the earliest texts must have been composed after the 6th century BCE. And they don't mention Asoka anywhere so must have been composed before the middle of the 3rd century BCE. And so on. But many facts are lost to history and we only have the later tradition to go on.

The Buddha likely spoke in several dialects that were quite similar to Pali. He was immensely well traveled for his time, so in his travels he likely adopted the native dialect to be better understood by the locals. His words were only a small part of his teaching - his enlightened presence and conduct were likely better vessels of his teaching.

The Pali canon is a consolidation of his talks, created only after his death. The content is very likely the same, but the rendition is only as Ananda and other disciples remembered him. The standardized repetitive form was created as an aid to rote memorization and oral rendition. There was certainly doubt in their minds as they set down the teachings that they'd not be able to replicate the vastness of the Buddha's being in mere words, but all the same they resolved to make a sincere effort, and the Canon that emerged was a result of seven months of deliberation.

See https://en.wikipedia.org/wiki/First_Buddhist_council

Pali (Pāli) is a Prakrit native to the Indian subcontinent. It is widely studied because it is the language of many of the earliest extant literature of Buddhism as collected in the Pāli Canon or Tipiṭaka and is the sacred language of Theravada Buddhism.
Many Theravada sources refer to the Pāli language as "Magadhan" or the "language of Magadha". This identification first appears in the commentaries, and may have been an attempt by Buddhists to associate themselves more closely with the Maurya Empire. The Buddha taught in Magadha, but the four most important places in his life are all outside of it. It is likely that he taught in several closely related dialects of Middle Indo-Aryan, which had a high degree of mutual intelligibility. There is no attested dialect of Middle Indo-Aryan with all the features of Pāli. Pāli has some commonalities with both the western Ashokan Edicts at Girnar in Saurashtra, and the Central-Western Prakrit found in the eastern Hathigumpha inscription.
Whatever the relationship of the Buddha's speech to Pāli, the Canon was eventually transcribed and preserved entirely in it, while the commentarial tradition that accompanied it (according to the information provided byBuddhaghosa) was translated into Sinhaleseand preserved in local languages for several generations. In Sri Lanka, Pāli is thought to have entered into a period of decline ending around the 4th or 5th century (as Sanskrit rose in prominence, and simultaneously, as Buddhism's adherents became a smaller portion of the subcontinent), but ultimately survived. The work of Buddhaghosa was largely responsible for its reemergence as an important scholarly language in Buddhist thought. The Visuddhimagga, and the other commentaries that Buddhaghosa compiled, codified and condensed the Sinhalesecommentarial tradition that had been preserved and expanded in Sri Lanka since the 3rd century BCE.

Source: https://en.wikipedia.org/wiki/Pali
See also,  http://www.vridhamma.org/Pali-Overview-94-Seminar

I would like to state an ongoing objection to using wikipedia as a source.

I respect that objection, however any encyclopedia is a starting point for research, not an ending point. Wikipedia is increasingly considered good enough evidence by many journalists, policy makers. Though not suitable as a primary source when writing a research paper, several research papers increasingly lean on Wikipedia as a tertiary source. For this forum, I believe Wikipedia is suitable since an answer relying on original sources in printed books is hard to follow up on. Perfect must not become the enemy of good.

If you are still unconvinced I'd encourage you to start a thread on meta where you can state your concerns in greater length for others to weigh in on. Thanks.

This thread continued on http://meta.buddhism.stackexchange.com/questions/1640/wikipedia-as-a-source

According to the Buddha's advice, early Buddhists composed and taught the Suttas in their respective vernaculars. So there was not an official language of Buddhism. Wherever Buddhism went, it adopted the local language of that region. Now, Pali was the native language of the region around Vidisha in central India as the Girnar inscription shows. The mother of Ashoka's son Mahendra was form Vidisha. Also, Mahendra started his missionary journey to Sri Lanka from here to reach the West Coast and sail to Sri Lanka. At that time, there was no written canon. So Mahendra just took some monks with him who knew different parts of the canon. Since these monks were from Vidisha region, they learned the Suttas in Pali and they taught these Suttas to the Sri Lankans who mistakenly thought that Pali was the mother tongue of the Buddha. Since then, this belief has been common in the Theravada countries. But it is clear from the above that there is no basis in this belief. The Buddha never went to Vidisha in his lifetime. He was a native of Koshala. So it is likely that he spoke the Koshalan dialect of Prakrit.
Pali canon is the canon of the Theravada school which was just one of the many (the traditional number is eighteen but this is clearly an approximate one, the actual number may vary slightly) schools of sectarian Buddhism. These schools started to originate probably one and a half century after the demise of the Buddha. This schism process lasted till the birth of Christ and even afterwards. At present, we do not have the canon of the non-sectarian Buddhism. So we cannot expect whole of the Pali canon as verbatim words of the Buddha. Even so far as Theravada is concerned, the Pali canon was written in the last half of first century BCE, long after the formation of Theravada. Before that it was transmitted orally and might have been changed.

According to renowned Tripitaka translator and scholar Bhikkhu Bodhi (from here):

Scholars regard this language (Pali) as a hybrid showing features of
  several Prakrit dialects used around the third century BCE, subjected
  to a partial process of Sanskritization. While the language is not
  identical to what Buddha himself would have spoken, it belongs to the
  same broad language family as those he might have used and originates
  from the same conceptual matrix. This language thus reflects the
  thought-world that the Buddha inherited from the wider Indian culture
  into which he was born, so that its words capture the subtle nuances
  of that thought-world.

Please also see the book "The Authenticity of the Early Buddhist Texts" by Bhikkhu Sujato and Bhikkhu Brahmali, as it contains a detailed analysis on how authentic are the Pali suttas. It may not be verbatim, but it is mostly authentic, according to their analysis.
The abstract states:

This work articulates and defends a single thesis: that the Early
  Buddhist Texts originated in the lifetime of the Buddha or a little
  later, because they were, in the main, spoken by the Buddha and his
  contemporary disciples. This is the most simple, natural, and
  reasonable explanation for the evidence.
Our argument covers two main areas:
   1. The grounds for distinguishing the Early Buddhist Texts (EBTs) from later Buddhist literature;
   2. The evidence that the EBTs stem from close to the Buddha’s lifetime, and that they were generally spoken by the historical
  Buddha.
Most academic scholars of Early Buddhism cautiously affirm that it is
  possible that the EBTs contain some authentic sayings of the Buddha.
  We contend that this drastically understates the evidence. A
  sympathetic assessment of relevant evidence shows that it is very
  likely that the bulk of the sayings in the EBTs that are attributed to
  the Buddha were actually spoken by him. It is very unlikely that most
  of these sayings are inauthentic.

The section called thesis states:

That most of the Early Buddhist Texts (EBTs) are authentic.
That the EBTs were edited and arranged over a few centuries following the Buddha’s demise. The texts as we have them now are not a
  verbatim record of the Buddha’s utterances, but the changes are in
  almost all cases details of editing and arrangement, not of doctrine
  or substance.
That the inauthentic portions of these texts are generally identifiable.
That the above points are supported by a substantial and varied body of empirical evidence.
That the denial of authenticity is a product of excessive and unreasonable scepticism, not evidence.

The most important and genuine sayings are preserved, albeit scattered around, in Pali Tripitaka. Most are latter commentaries though.


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How to accept and surrender to the mind's non-acceptance of doubt and ill-will?
I have a question that I would like some input on.
Lately, I have been able to see the fruit that total acceptance and surrender can bring to one's experience. I have tasted moments of pure joy, compassion, and equanimity. In these states, everything appears very clear and I'm able to rest with the experience and not cling on to these pleasant feelings. Everything I have read about and heard from teachers seems crystal clear. Perception is completely altered and the mind is clear.
Inevitably, these experience fall away and hindrances make their way back into the mind. In my experience, the hardest of these hindrances to overcome is doubt. Once doubt enters, it's easy for ill-will to follow as well as other hindrances.
Intellectually, I'm aware of the Four Noble Truths and that desire causes suffering, and even that desire for the cessation of desire causes suffering. I'm aware that aversion to whatever state of mind and feelings are currently present only perpetuates them. However, when the pleasant states are gone and hindrances arise (especially doubt), I begin to question everything I know.
I have told myself and written down tips and advice on how to handle these kinds of situations when my mind was unhindered. Even though I know in my heart to trust my own words and experiences, when doubt is strong enough, everything is deluded.
I don't have a single question, but I would appreciate input on how to handle strong moments of doubt and ill-will towards that doubt. In the past, I have always managed to accept the feelings and allow them to pass, which is what I know I need to do, however in the moment it can be incredibly difficult.
The toughest thing for me to work with is getting angry at myself for not accepting the unpleasant feelings for how they are. I know that to move past them, I need to accept non-acceptance, but that is always easier said than done. This leads to a downward-spiral of aversion towards aversion of doubts.
Any words, tips, or tools you guys have are so very much appreciated.
Edit: I apologize if this is too much of a discussion-based question without a real definitive answer. I am new to SE in general, so please forgive me if this isn't an appropriate question.

Hi, and welcome to the site. Here, unlike many of the other SE sites, people will try to answer almost any question. If you're used to other SE sites then you'll know they have various reasons why a question might be closed; but we have an old specific meta-topic here (though it's long and maybe not worth reading) about how or why we try to handle such difficulties, instead of closing a question.

Any words, tips, or tools you guys have are so very much appreciated.

Does it help to remember that "doubt" and "identity view" belong together? If they eradicate together (at the same stage) then maybe they arise together.

Even though I know in my heart to trust my own words and experiences, when doubt is strong enough, everything is deluded.

Isn't 'identity view' a bit deluded too?
So like, "I am doubting" and "here is myself experiencing doubt": just forget it. Experience it, recognize it, remember it's delusive, and put it away, do or be without it.
I (subjectively or as an analogy) experience some kind of brain storm that's like an electrical short circuit, that draws all the electric current and does nothing. If it persists and I recognize it then I deliberately blow the fuse on it: i.e. recognize it as a fault, switch off the current (stop feeding it), try to see a bigger, more stable, more useful picture.
I label/name that storm "a thicket of views", which the suttas say is associated with views about self.
In summary I'm trying to suggest that if you're experiencing "doubt" then maybe you're experiencing "identity view"; maybe you can already handle identity view, and/or recognize it as a cause of doubt.

I would appreciate input on how to handle strong moments of doubt and ill-will towards that doubt.

According to the Wikipedia article I cited above, doubt and identity-view go together but ill-will may remain until later. So don't be surprised if there's ill-will.
I mean, you're saying "ill-will towards doubt and delusion". I suppose you have to be free of the doubt and delusion you talked about, first and foremost; and once you see things clearly then you can (perhaps literally) "sort out" the ill-will (maybe ill-will goes after delusion stops, like you say it comes after delusion starts).
This advice is partly based on the idea that "right view" is the first (or if it's called "right knowledge" then it's also nearly the last) factor on the path.

Thank you, this is very helpful. I will treat such moments like the "brain storms" that you referred to. It's also very helpful to know that doubt and identity view arise together.

Dukkha comes from mismatch between "what is" and what you think "should be". Keep repeating this until it sinks in :)

What you resist persists, what you embrace dissolve. The more you will resist your tendancy to doubt, the more you will experiment doubt. Let it be, even if unpleasant, and cease to resist it in the present moment. It will then gradually go away.
Yann

Hi Yann and welcome to Buddhism SE. We have put together a Guide and a Resource section.

Practice the Four Immeasurables, the four divine abodes.
Potential practice methods:
There are four, pick one a day and spend a few twenty-minute sessions meditating on it.
Loving-kindness / loving-heartedness (metta)

Empathic/empathetic/sympathetic joy (mudita)

Compassion / "to suffer with [and yearn to relieve]" (karuna)

Equanimity = deep equipoise (upekkha)

They are called Brahmaviharas which translates roughly to "divine fields of becoming" or "godly dwellings"
Hindrances and afflictions are overcome by wise effort.

source: Stack Exchange

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sort: votes


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Is shellfish aquaculture considered a wrong livelihood?
I am currently employed on an aquaculture farm that specializes in clams and oysters. According to our modern system of taxonomy, both of these organisms are considered animals. I also know that a profession in which one trades animals is not right livelihood. However, according to this site, clams and oysters don't really have brains. Furthermore, according to wikipedia, it would seem that the nervous system of the mollusk doesn't really function to sense pleasure or pain. So, I am wondering- does trade in shellfish count as wrong livelihood? If so, how does one determine what is an animal and what is not according to Buddhism? If one is meant to go by whatever their respective society defines as an animal, surely this definition will change and therefore make this aspect of right livelihood unreliable, right?
Thankya

The Vanijja Sutta is the standard definition of "wrong livelihood" and is, as you saw, not specific. It says, in its entirety (at least in this translation),

"Monks, a lay follower should not engage in five types of business. Which five? Business in weapons, business in human beings, business in meat, business in intoxicants, and business in poison.
"These are the five types of business that a lay follower should not engage in."

FYI in this commentary on the Vinaya, on page 308, it says,

Raw flesh and blood are allowed at Mv.VI.10.2 only when one is possessed
by non-human beings. Thus, in more ordinary circumstances, one may not eat
raw fish or meat even if of an allowable kind. This would include such things as
steak tartare, sashimi, oysters on the half-shell, raw eggs, and caviar.
Furthermore, even cooked fish or meat of an allowable kind is unallowable if the
bhikkhu sees, hears, or suspects that the animal was killed specifically for the
purpose of feeding bhikkhus (Mv.VI.31.14)

So, apparently, according to this, oysters (and eggs and caviar too) are considered flesh or meat.
Whether you're vegetarian is slightly up to you. This article too (of unknown authority) says not to "steam live clams or eat live oysters" but explains why it's seen as relatively OK to buy meat under certain circumstances.
There was an argument between the Buddha and Devadata apparently, with the Buddha's not mandating vegetarianism because he didn't want the Sangha to be difficult for lay people to support.
FYI one of the criteria for the "no killing" precept is whether you're conscious that the being is alive and that you intend to kill them: killing someone by accident if you thought they were already dead, for example, wouldn't be breaking the precept. So, who knows, maybe it's partly up to you decide or to be aware of whether they count as "animals" or "meat" or "sentient".
I found this modern paper which claims that they're not especially sentient, but I doubt that's canonical.
And some people would have you know that even being a vegetable farmer or crop farmer presumably wouldn't prevent the deaths of worms and possibly field mice and so on.
Anyway, good luck with finding a solution.
And don't know any context to the Vanijja Sutta (it's in the Anguttara Nikaya as a list of five things). You'd think that if "Right Livelihood" were important enough to be in the Eightfold path then it would be better defined; but maybe it's better defined for monks than it is for laypeople; or maybe it's tangential to the main message, i.e. the Buddha's messages wasn't especially about right livelihood.
The book The Buddha's Teachings on Prosperity which is a bit of compendium of rules for lay people doesn't talk about "right livelihood" exactly but does say "don't destroy life". It claims that the Gihi Sutta (although I don't see this there) says that you should avoid trapping animals unless you're too sick or weak to farm.

Mr/Mrs Ian

"A lay follower should not engage in five types of business. Which
  five? Business in weapons, business in living beings, business in
  meat, business in intoxicants, and business in poison." AN 5.177
Pañcimā bhikkhave, vaṇijjā upāsakena akaraṇīyā. Katamā pañca:
  Satthavaṇijjā, sattavaṇijjā, maṃsavaṇijjā, majjavaṇijjā,
  visavaṇijjā. Imā kho bhikkhave, pañca vaṇijjā upāsakena akaraṇīyāti.

Manussa would be human. An older translation of it had beings. It is unknown and unreasonable why it has been changed to "human". Atma assumes that it might be an commentary comment, developed in times when the Monks became to be more domestics and in deeper relation with those trading with animals.
One may consider this in this relation:

"There is the case where the disciple of the noble ones — using the
  wealth earned through his efforts & enterprise, amassed through the
  strength of his arm, and piled up through the sweat of his brow,
  righteous wealth righteously gained... Adiya Sutta: Benefits to be Obtained (from Wealth)

How could one enjoy his wealth knowing that it is an the cost of others?
And never ever start to think in this unwohlesome deeds justifying Mohayana development of "sentient beings". Such was never said by the Buddha. Living being, what breaths, what ever has 1, 4, 5 Aggregates. 100 Years ago people still said that animals have no feelings... or this or that being is lower, because of this and that. Even to destroy a live of a being, as (and incl.) small as the egg of a bedbug, is mentioned to be a cause of being a fault. So what ever one perceives as being a living being, one does good not to cause harm or even takes its live, acknowledge such, or move others to do so.
Actually if somebody begins to have doubt and feels his/her conscience, its a great sign and one should follow this Governing Principles
Consider that a yogi or contemplative (not to speak for a Bhikkhu/Bhikkhuni, who are even not allowed) not even keep animals or accept them.
And to ask your self in regard of livelihood, do I harm, do I use other beings, even against their will, is it dishonest livelihood, am I honest in reflecting this?
The Buddha did not talk much on the topic knowing that people are not easy able to change their ways of life, but since one has open all doors, knowing the problems before choosing a job, one does good in considering a lot and give certain possible wealth and "security" for a good sleep and the possibility to develop the path.
(Note: this answer has not been given with the agreement to be means of trade or the purpose of/for trade and/or keep people trapped and bound. How you handle it lies in your sphere, but does not excuse the deed here either.)

I asked myself the same thing once so wanted to know what makes a plant and what makes an animal.
http://www.mcwdn.org/Plants/PlantsDiffer.html
.. if in doubt ask yourself, could I be reborn as this? In your examples I would say yes.

It seems that there is a wide opinion of what is allowable on the Buddhist diet. Some are strict vegans who will only take the fruits of plants, not the roots. Some practice practice pescatarianism, eating only fish. Personally, I follow the bodhisattva vows of the Brahmanet Sutra which says you shall not eat the meat of "sentient" creatures. I do not count oysters as sentient. Therefore, depending on which moral code you wish to follow, I think your profession is safe.

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Are there different factors for access concentration depending on which jhana an individual is entering?
I have heard that a practitioner does not go from first jhana directly to second jhana or from second jhana directly to third jhana and so on. Instead, they go through momentary and access concentration to get to first jhana; then they drop out of first jhana and go through momentary and access concentration to get to second jhana and so on. First of all, is this correct, am I totally wrong or is there debate with regards to this?
Secondly, do the factors of access concentration change depending on which jhana someone is trying to enter?

I can only answer first part of your question, i.e. if a meditator returns to access concentration between Jhana-states.
You are correct in that understanding. Here is a quote from the book "Practicing The Jhanas" by Tina Rasmussen and Stephen Snyder, which describes access concentration and that between entering the different Jhana-states the meditator returns to access concentration. Highlights in the quote are made by me:

ACCESS CONCENTRATION
Meditators can eventually attain access concentration using either type of momentary concentration practice—samatha or vipassanā. However, samatha practices are more likely to lead to access concentration because of their more stable nature. Access concentration is characterized by the significant reduction or complete dropping of the five hindrances and the arising and strengthening of the jhāna factors. For most people, a period of intensive practice is required to reach access concentration. In access concentration, the meditative experience becomes smoother, easier, and more pleasant because of this lessening of hindrances and the arising of the powerful and blissful sensations of the jhāna factors. This allows meditators to meditate longer and progress more easily in the practice.
It becomes a positive, self-reinforcing loop.It is easy to confuse momentary concentration with access concentration. One difference is that with access concentration, the meditator’s continuity with the object is much longer and more stable over time. Another difference is that with access concentration, the object is much more energized and “bright.”Most of the practices outlined in this book are samatha practices specifically designed to settle the mind and develop laserlike awareness, leading eventually to full absorption into the jhānas. Examples of samatha practices designed to develop access and absorption concentration are ānāpānasati meditation (as presented by the Venerable Pa Auk Sayadaw), the kasiṇas, thirty-two-body-parts meditation, skeleton meditation, and the bramavihāras (sublime abidings).
As access concentration develops, but prior to full absorption, it is also easy to confuse access with absorption concentration. In access concentration, the jhāna factors are present but insufficiently strong for full absorption into jhāna. (The differences between access and absorption are described below.) Even after a meditator has experienced full jhāna absorption and begins to move through the practice progression, access concentration continues to be used. With progression to each successive jhāna, the meditator first experiences access concentration as the awareness orients to the new experiences and increases in stability.
-- Practicing The Jhanas, p. 73-75

To make sure we're on the same page, terminology wise:

Factors - these are the factors or qualities of the various Samatha Jhanas - joy, well-being, equanimity etc.
Momentary Concentration (Kanika) - ability to stay focused on moment-by-moment arising and passing of phenomena.
Access Concentration (Upacara) - ability to stay focused on on a somewhat contrived stable object i.e. the breath, color, shape etc.
Absorption (Apana) - stable, one pointed mental state.

The Jhanas themselves are a continuum of mental states that don't exist as separate discrete entities. They are mental states that unfold depending on where in the continuum your experience lies. Somewhat like a rainbow - it is made up of different colors that have different qualities but on close examination they blend together seamlessly. The mind moves through these qualities in Jhana by focusing on the different qualities.
Generally speaking, deepening of access concentration increases the chances of the unfolding of Jhana. Once the first Jhana is established no special factors of access concentration are required to move into the second. The qualities of the first Jhana are :- pleasant sensations, joy, and sense of well-being. The meditation object of concentration (Samatha) is left behind and the minds merely abides (is absorbed in the Jhana qualities). When shifting through the Jhanas the focus just changes to subtler and subtler factors - from sensations to joy, from joy to well-being, from well-being to equanimity. So IMHO there is no dropping out of Jhana to gain access to next etc. or special factors of access concentration required. Five factors help to navigate the jhanas:

Directed attention (Vitakka) - directing the attention to a particular perception.
Sustained attention (Vicara) - sustain attention on an object.
Rapturous interest (Pita) - When vitakka and vicara are steady, a feeling of lightness and pleasure naturally occur.
Deep ease (Sukha) - Sukha is a quality of happiness that is much quieter and smoother than piti.
One-pointed attention (Ekaggata) - Ekaggata’s characteristic quality is to lock on to the chosen object with an intimacy that rivets the attention, stills the mind, and settles into unwavering focus.

These five elements of concentration — connecting, sustaining, rapture, joy, one-pointedness — take center stage during jhanic experience. Each level of absorption has its characteristic blend of these factors. Skill in entering and maneuvering through the levels of absorption depends upon cultivating these five factors. Catherine, Shaila. Focused and Fearless: A Meditator's Guide to States of Deep Joy, Calm, and Clarity (p. 108). Wisdom Publications.

Momentary concentration is cultivated specifically for vipassana practice but can result in Jhana as well. Daniel Ingram:

The vipassana jhanas differ from the concentration jhanas (samatha jhanas) in that they include the perception of the Three Characteristics, rather than the “pure” samatha jhanas that require ignoring the Three Characteristics to get them to appear stable and clean. However, the two may share many qualities, including very similar widths of attention and other aspects.


text:
Intuition in Buddhism
I was told that intuition is not to be cultivated in Buddhism. Intuition is blind and not to be followed. Following something blind can be quite dangerous.
At the same time, there is a book called 'Intuitive Awareness' by Ajahn Sumedho.
So I'm confused now which one is the correct one. The more mindful you are, more things are opening up, you understand more things, some answers just come without any reasonable explanation.
Can someone explain Buddhism's view on intuition? Thanks.

Hi Steve and welcome to Buddhism SE. You are asking a good question. There is just one thing. Asking about one's experience tends to be opinion-based which this format is not suited for. I changed the last sentence in your question to better reflect the stack exchange format. Feel free to correct it if it can be improved.

This is probably just a case of a word having many (conflicting) uses.
Intuition is an elusive word. It seems we often associate it to a kind of feeling about something. Because that "kind of feeling" is also elusive and could be pretty much anything, it may be regarded as unreliable. Perhaps this explain why you were told it is not something to be valued.
However, intuition can be used to describe not-so-elusive kinds of knowledges, like tacit/implicit/non-verbal knowledge we all use daily (e.g. intuitively knowing where the north is, or how to solve a puzzling problem).
Finally intuition can also mean some kind of immediate knowledge of reality. I found the following dictionary descriptions interesting:

direct perception of truth, fact, etc., independent of any reasoning process; immediate apprehension.
a fact, truth, etc., perceived in this way.
a keen and quick insight.
the quality or ability of having such direct perception or quick insight.
pure, untaught, noninferential knowledge.

This description is close to wisdom (but in Buddhism, it's a little more specific than that: see paññā/vipassanā, yoniso manasikāra and yathā bhūta ñāna dassana). And wisdom is something that has been systematized in Buddhism: there is both a large body of practice and evaluation. One can speak of attainments, higher and lower wisdom. One can identify when one's wisdom is lacking, and when it improved. Finally, one can practice to develop it.
"Mere intuition", on the other hand, as just "some feeling", has a high risk of being just this: a mere feeling. And mere feelings are often wrong. And once wrong or right, we are lost as to why. To explain it, one ends up creating some sort of (creative) theory or borrowing from some religious tradition or superstition ("the channeling with spirits was not clear", "I ate meat at an inappropriate time", etc.), which further tax one's beliefs, and might bring one closer to the blindness referred to.

Buddhism likes reason and origin, pratityasamutpadaPratītyasamutpāda which tells that nothing happens without a reason. I do not think any sutta contains the term intuition, what Buddhism is interested in is pratityasamutpada when arriving at conclusions. The scientific method also has reason, but is more rigid than pratityasamutpada. More open and more realistic framework of pratityasamutpada can discover more than what scientific method discovers. If your current scenario fits with this frame pratityasamutpada, you can agree with it.
Simply I agree with Ajahn Sumedho, even without reading the book, that is via intuition. First of all we have six senses, not five senses. We cannot forget the mind. People should agree with the mind, the correct mind. You are more successful when using the mind because you cover a wider range, you are using your all six senses. I think you should continue according to the book. Some sources tell the sixth sense is intuition, but I am not sure whether mind in Buddhism and intuition in psychology, both being the sixth sense in respective fields refer to the same. I have read a lot of psychological stuff; books, articles and quotes etc. And I have a fair knowledge in basic Buddhism also. From what I have read, in a psychological or cognitive sense, there is no clear definition or agreed upon definition on intuition. I have read so many bad things on intuition in an organizational behavior textbook while Albert Einstein, Immanuel Kant and other great men have praised intuition a lot. If you go to mbti classification, most of those so called great men are intuitive types.
I have not met intuition in a Buddhist source so far, but it is a good thing when backed up with some reasoning and experience of the individual. In a psychological sense, some men are gifted with intuition, they already know things, so they can read between lines, avoid choosing a tree over the forest and learn faster and move ahead faster. When you mediatate, when you read stuff, when you practice stuff, your intuition develops. You know more things and you have it in practice. Such a developed intuition can be believed and it should be chosen over a few ordinary tangible things we see at the moment, because intuition covers an wider range of experiences and knowledge. But yeah the people who don't have a developed intuition should not trust it, but when it is developed, should trust it. Intuition is not blind but very powerful when it is backed up with experience and knowledge which are mostly acquired via the other five senses. In fact, if you do not trust the intuition, you will stagnate. So move ahead reading and practicing the book. Hope you got some clarification.

Thanks all for your reply.
I too think intuition is pretty illusive word.
When someone encounters a situation, his normal reaction is like this. But in other occasion, one pauses for a moment instead of responding immediately. In this moment of quiet mind, he knows how to respond appropriately for that particular situation. This extends to other human being, instead the habit of judging someone immediately, he pauses for a while and look inward.

The moment of pause makes him perceive the reality more ‘as it is’, more balance view instead of negative judgemental attitude during a conversation toward a stranger he just met, for example. With silence, understanding over a situation or a person is more, preconceived notion is less but also accompany with  a ‘hint’ as to how to appropriately respond to that situation or person. I don’t know how to call this experiences, is this an intuition or something else?
Does anyone know if this kind of experience explained in the Sutta?

I do not know whether intuition is found in any sutta. But generally, intuition corresponds to the big picture and interrelationships. It can be correct or incorrect, the thing is people have good, bad or neutral attitudes on things. But an optimistic or greedy mind tends to see only the good as the first hint or picture, a pessimistic or a mind with too much aversion will first see a hint of bad things only. An ignorant mind will notice nothing. So I think intuition differs from person to person in various degrees, but it does not show the right picture, but may give a part of the picture.

I like how you say that intuition develops as we develop. I would say this is like cognitive development from Concrete Operations to Formal Operations to Post-Formal. Larger and larger part of the mind all working in unison. "Recruiting".

Thank you and I can agree with all you said. I think intuition corresponds more to Post-Formal operations.

@DewminiGunasekera
In other words, it's a delusion? I'm wondering if this has any relation with strong concentration in Jhana, is that some kind like delusion as well since people who have developed this ability can penetrate into other people's mind. I just think it's similar since rational thinking is not involved in both of them.

Just like every other senses are delusional, intuition too. I believe intuition in psychology comprises of terms like mind, consciousness etc which are terms in Buddhism. Intuition does have a positive relationship with meditation. So we can PREDICT Jhana has a relation with intuition. Penetration into other minds is not accepted by Lord Buddha. I believe Intuition and Jhana both have rational processes behind, may not be perfectly rational, but has a degree of it. Intuition and thinking can be both rational and/or irrational, what we should worry about is rationale, not the method behind it.

As I see it, Awareness consists of Conscious awareness and Unconscious awareness. Countless things are going on in our minds all the time that we are not conscious of, yet they can come to consciousness when needed. A visual model would be an Iceberg: most of it is below the waterline, like most of our sensing and cognition is not conscious to ourselves. (The 'unconscious' is conscious of itself and knows what it is doing. Animals, for example, have barely any 'consciousness', yet they function just fine.)
As people develop, they grow in consciousness, such that more and more of their awareness is known to their conscious mind, as if the Iceberg was to slowly rise from the water until it was mostly or entirely in the air. Realized people do this.
Intuition, then, is simply that your 'unconscious' (the bulk of your mind) is doing its job of sensing, filtering and assessing below decks and sometimes it sends an alert to your conscious mind, which you are free to ignore (at your peril). It is not infallible but it is the best thing we have for staying safe and happy, until we become more fully Realized. Make sense?
This is related to the idea of Recruiting, where as we develop, we can use larger and larger proportions of the mind / brain / consciousness / whatever and awareness deepens, widens and becomes more full and less about sequentially processing ideas. See the movie LUCY. There is a nice post about: Recruiting "points of view in the mind" out there.
A simple example: I was walking in the woods with someone when I suddenly stopped and stooped down to peer at a spider that was about 3 mm across (1/8 inch). My friend asked how on earth I had noticed it while walking on a sandy, rocky, leaf-strewn path without looking down, and that most people could not have seen the blessed thing even if they were looking right at it! (I am over 6 feet tall). I said, "it was moving and it caught my eye." Since I try not to step on things in my walks but I don't wish to spend all my thoughtpower on that, I have developed a "process" that looks for things throughout my visual range (spiderwebs?) and notifies me. You could call it Intuition as much as anything else.
What has this to do with Buddhism? "I have no idea" (from the movie LUCY). See my profile also.

the modern definition of intuition is instinctive knowledge (without using the rational process), or impression, hunch, suspicion - quite far apart on the spectrum.  The former indicates gnosis, while the latter implies strong belief.  Regardless, here's a good quote from the discourse Kitagiri Sutta:

“Monks, I do not say that the attainment of gnosis is all at once.
Rather, the attainment of gnosis is after gradual training, gradual
action, gradual practice. And how is there the attainment of gnosis
after gradual training, gradual action, gradual practice? There is the
case where, when conviction has arisen, one visits (a teacher). Having
visited, one grows close. Having grown close, one lends ear. Having
lent ear, one hears the Dhamma. Having heard the Dhamma, one remembers
it. Remembering, one penetrates the meaning of the teachings.
Penetrating the meaning, one comes to an agreement through pondering
the teachings. There being an agreement through pondering the
teachings, desire arises. When desire has arisen, one is willing. When
one is willing, one contemplates. Having contemplated, one makes an
exertion. Having made an exertion, one realizes with the body the
ultimate truth and, having penetrated it with discernment, sees it.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
Returning to the marketplace - examples
In the Ten Ox Herding Pictures of Zen the final picture is commonly depicted as returning to the marketplace. Enlightenment is said to be doing the most ordinary things in a most extraordinary way.
It is very different at many levels from the Theravada model of an Arhat who recollects past lives, walks through walls, flies in the air and so on. Though there are references to vasanas which prevent the Arhat from Buddha like perfection, they are not commonly what comes to mind when one thinks Arhat. It is reinforced by the belief that one who has such attainment will leave the family, never have romantic worldly ideas, become a monk and generally be holy, strictly confirming to popular ideas of what is holy - i.e separate from this undesirable world of samsara.
The Zen model doesn't even have the label Arhat that makes such attainment separate and special. Zen masters are of course famous for doing silly things like playing with kids, drinking wine, teaching in whore houses and so on. I've read similar things in the Tibetan tradition. Though it's another matter that most Zen masters obsess with lineage, robes, proper form and such.
I'm looking for sutras, books, biographies or examples and generally any text that deals with returning to the marketplace in various traditions. Any tradition is fine.
Does the Theravada canon have such ideas anywhere at all? Perhaps Tibetan?
Thanks.

Does the Theravada canon have such ideas anywhere at all?

This is a far-fetched example which barely answer your question but IMO the Buddha himself kind of returned to the market-place: not as a tradesman nor even a customer, but he did leave his solitude.
The description could almost fit him:

In the World

Barefooted and naked of breast, I mingle with the people of the world.
  My clothes are ragged and dust-laden, and I am ever blissful.
  I use no magic to extend my life;
  Now, before me, the dead trees become alive.
Comment: Inside my gate, a thousand sages do not know me. The beauty of my garden is invisible. Why should one search for the footprints of the patriarchs? I go to the market place with my wine bottle and return home with my staff. I visit the wineshop and the market, and everyone I look upon becomes enlightened.

Any resemblance can't be entirely accident, presumably, to the extent that he was ever a role model for Buddhist enlightenment.
A few things seem to me anachronistic.
Magic
"I use no magic to extend my life" -- is that a reference to (rejection of) some Taoist-immortality-magic or -obsession: which, I'm not acquainted with, but might have been important when it was written?
Wine
The "wineshop"?
Wine is forbidden in Islam too, but apparently some Sufis use "wine" as a metaphor for a divine love and loss of ego. That's esoteric (and orthodoxly a heresy) in Islam (it also reminds me of a family story: that when my grandfather bought a house in Morocco he met a "hereditary saint" there who was allowed to drink wine because the wine would turn to water in his mouth), but really I don't know anything esoteric especially about Buddhism. Apparently there was a Sufi doctrine which said that, "Drinking 'wine' depends: on how much, and who with", but beware I think that advice is Delphic.
Another idea is that some of the versions of the ten bulls talk of carrying a "gourd", depicted as (or, who knows, perhaps mistaken for) a wine gourd: but which (a gourd), someone else wrote, is a metaphor for emptiness.
Sunyata might be a bit anachronistic too, i.e. a tenet developed in slightly later schools.
Non-duality
It's a bit difficult to imagine the Buddha pulling a pint in the pub with his friends. If I see someone doing that though, then as long as they're not doing harm I'm conditioned not to say something like, "You're a bad man: you shouldn't be drinking."
Is that what "everyone I look upon becomes enlightened" means, i.e. non-duality, and to whatever extent I hope to become enlightened, other people become so too? I mean there are two ways to see that: being "looked upon" (or talked with) helps to lead the seen person to enlightenment; doing the looking helps the seeing person see there is enlightenment (perhaps some "Buddha nature") already.
On the other hand maybe drinking is harmful, and if I were wise and kind and selfless then I would mingle with them there?
Anyway that leads to this other answer about non-duality which I think you already know, which says there are real differences between Theravada and Mahayana practice. And so I present that answer as saying, "No, I don't think you'll find exactly the same 'returning to the marketplace' within the Theravada Sangha."

It is reinforced by the belief that one who has such attainment will leave the family

One of the Zen stories I admire is Nothing Exists. I like it because it reminds me that it's not to do with theorizing about the nature of external phenomena, but it's more about being prepared to behave myself.
There's a quote I read once, I haven't found it again since, someone was asked "Why won't you become a Christian?" and replied, "If you mean 'Christian' like your Christ, it's because I don't have the courage. If you mean 'Christian' like you, it's because I wouldn't want to be."
Does that make sense, assuming you know the Christian metaphor for marriage? I don't know whether you are or have ever been married, but how could you expect to control two people if you don't even control one?
Actually I have the belief that Siddhartha left his family, not because he had such attainment but because he desired that attainment.
Conversely, Is That So? might be a story of someone who already has some attainment and subsequently acquires a family.

I think the larger problem here, which you hint at, is trying to ascribe a Mahayana ideal onto the Pali canon Buddha.  While there is a type of Bodhisattva mindset in the elder tradition, it doesn't really find it's fleshed out mythic ideal until much later - c. 8th century C.E. at Nalanda in the writings of Shantideva.  Analyzing the Buddha in the context of much later Mahayana is like trying to fit the image of Christ back over atop Moses.  If you force it, it works to some extent. The archetype is, however, completely different and serves a very different purpose.

This isn't really an answer - more of a comment.  I'll just end up pressed for space if I add it as such.  I think there is a certain presupposition that the person "returning to the market" actually left the market in the first place.  I think all traditions have this archetypal ideal of the ascetic who wanders into the wilderness, adopts the homeless life and then returns as a fully formed, enlightened sage.  It may work like that in some cases.  I would actually say that is an exception these days assuming that ideal every really existed in the first place.
Practice happens everywhere.  We all know that.  The thing is, it rarely looks like the great mythologies.  For every Buddha and Jesus and Muhammad wandering around in the wilderness and talking to burning things, there are billions of practitioners just finding better ways to talk to their daughter and smooth out relationships in the workplace.  No one writes stories about these folks because what they do is so mundane.  Their actions don't light up our brains in the same way that those great mythologies do.
Practice isn't something that happens "out there".  We don't find our enlightenment out on some sacred journey and come back to tell the tale.  There isn't one moment where we emerge as a fully enlightened being, come home to great fanfare, and start getting drunk with the butchers.  That's not even true of dai kensho.  Practice is here.  Practice is now.  Returning to the market is our practice.  It isn't something that happens bodily or sociologically or mythically.  It is something that happens in every instant of renewed awareness.

Does the Theravada canon have such ideas anywhere at all? Perhaps Tibetan?

Of course Theravada monks returns to the marketplace everyday. They use their daily alms round as an opportunity to be around the lay community. It's just that the method they use to help people is different. One won't see them drinking wine to help the drunkards or become whore house's patrons to help the prostitutes, etc. Moral virtues and spreading the Buddha's words are their methods of helping. If somehow the approach seems to be a bit passive or weak, then the story of Ven. Punna in SN 35.88 should clear things up for you:

(Ven. Punna wanted to go and live among the fierce people of Sunaparanta to help them. The Buddha wanted to test his resolve and here goes the dialogue):
"Punna, the Sunaparanta people are fierce. They are rough. If they insult and ridicule you, what will you think?"
"If they insult and ridicule me, I will think, 'These Sunaparanta people are civilized, very civilized, in that they don't hit me with their hands.' That is what I will think, O Blessed One. That is what I will think, O One Well-gone."
"But if they hit you with their hands, what will you think?"
"...I will think, 'These Sunaparanta people are civilized, very civilized, in that they don't hit me with a clod.'..."
"But if they hit you with a clod...?"
"...I will think, 'These Sunaparanta people are civilized, very civilized, in that they don't hit me with a stick.'..."
"But if they hit you with a stick...?"
"...I will think, 'These Sunaparanta people are civilized, very civilized, in that they don't hit me with a knife.'..."
"But if they hit you with a knife...?"
"...I will think, 'These Sunaparanta people are civilized, very civilized, in that they don't take my life with a sharp knife.'..."
"But if they take your life with a sharp knife...?"
"If they take my life with a sharp knife, I will think, 'There are disciples of the Blessed One who — horrified, humiliated, and disgusted by the body and by life — have sought for an assassin, but here I have met my assassin without searching for him.' 1 That is what I will think, O Blessed One. That is what I will think, O One Well-gone."
"Good, Punna, very good. Possessing such calm and self-control you are fit to dwell among the Sunaparantans. Now it is time to do as you see fit."

In Theravada, from what I have understood, there is no returning to the marketplace ( if I understand this ideea correctly) after one reaches the final goal, Nibbana.
There is another Sutta in which the Buddha is dwelling with Arahants and a brahman asks him if they all have supernormal powers, and the Buddha answers that not all of them have such powers. In Theravada, to be an Arahant you don't need to have superpowers. More knowledgeable colleagues can maybe point this Sutta name.
From Chabbisodhana Sutta, MN
[...]

“Bhikkhus, when a bhikkhu is one with taints destroyed, who has
lived the holy life, done what had to be done, laid down the burden,
reached the true goal, destroyed the fetters of being, and is completely
liberated through final knowledge, this is the natural way for him to
answer.
“‘Friends, regarding the seen I abide unattracted, unrepelled,
independent, detached, free, dissociated, with a mind rid of barriers.
Regarding the heard…Regarding the sensed…Regarding the
cognized I abide unattracted, unrepelled, independent, detached, free,
dissociated, with a mind rid of barriers. It is by knowing thus, seeing
thus, regarding these four kinds of expression, that through not clinging
my mind is liberated from the taints.’

[...]
I recommend reading the 33 Sermons on Nibbāna by Bhikkhu K. Ñāṇananda too see how Nibbana is seen in Theravada.
http://www.seeingthroughthenet.net/files/eng/books/ms/html/Mind%20Stilled.htm

The present set of thirty-three sermons on the topic of Nibbāna were originally delivered between 1988 and 1991 as fortnightly lectures at Meetirigala Forest Monastery of Sri Lanka by the Venerable Bhikkhu K. Ñāṇananda at the behest of the Venerable Mātara Sri Ñāṇarāma Mahāthera. They combine deep insight into the Dhamma with academic erudition, being based on copious quotations from the Pāli discourses that alternate with illustrative similes and useful indications for meditation practice.


text:
What is a wrathful Buddha?
In reading this answer to another question there were many references to "the peaceful and wrathful buddhas" in the quote from The Tibetan Book of the Dead. This is a tradition that I'm not very familiar with. Is it possible to explain what a wrathful Buddha is and how Buddhist teachings on considering anger as a poison might align with the idea of a wrathful Buddha? Thanks for any clarification on this.

Wrathful Buddhas (or wrathful gurus for that matter) are not actually angry, in the way untrained people are. In Vajrayana before we even reach highest tantra, we learn to transmute emotions. If you are not good at it yet, at the very least you should be able to transmute anger into headache. Once you reach some mastery though, you can transmute any emotion into pure energy. When you have direct insight into the nature of mind, emptiness, attachments, and emotions - you can ride a wave of energy and even display wrath (an appearance of anger) without really taking it seriously. This is then used as a tool in those cases that demand such approach. Like getting angry at kids, you are half faking it, half letting yourself get carried by anger - to add your show more weight.

That makes sense to me. The example of pretending to be angry with your kids is a familiar experience. Thanks. :)

According to the Wiki wrathful deities are representations of negative Kamma. It says that the wrathful forms of appearance is actually meant to lead beings towards enlightenment.

In Buddhism, wrathful deities are enlightened beings who take on wrathful forms in order to lead sentient beings to enlightenment. They are a notable feature of the iconography of Mahayana Buddhism and of Tibetan Buddhism, and other Vajrayana traditions in particular. A wrathful deity is often an alternative manifestation of a bodhisattva or other normally peaceful figure, making the representations of all human vices and atrocities. True to their name, in Tibetan art, wrathful deities are presented as fearsome, demonic beings adorned with human skulls and other bone ornaments.
The wrathful (or terrifying deities) are representations of negative karmas, in the same way as peaceful deities are representations of positive karmas. The symbol of the wrathful ones is the kapala, a half skull filled with blood.

This does not however answer what a wrathful Buddha is but if one follows the thought further one might suggest that the wrathful form of a Buddha might serve the same purpose as deities with wrathful appearances.
Here is another very interesting quote on Wrathful Forms:

Wrathful Forms
People who are not accustomed to the "language" of Tibetan Buddhist images are often surprised to see the wrathful deities for the first time.
One category of these is the herukas, a class of Vajrayana deities such as Chakrasamvara that is semi-wrathful with intimidating, even terrible, features.  They are represented as partially nude with an upper garment of human skin and a tiger skin around their hips.  They have a 5-skull headdress and carry bone rosaries, a staff or trident and a damaru (pellet drum) like the Hindu god, Shiva.  Herukas are described in Tibetan books as beautiful, heroic, awe-inspiring, stern and majestic.
From Judith Simmer-Brown's, Dakini's Warm Breath: The Feminine Principle in Tibetan Buddhism (Boston & London: Shambhala Pub., 2001,) 154-156:
"The heruka (tRak-thung) is a masculine deity, wrathful or semiwrathful, who represents the dynamic of compassion and skillful means in Tibetan tantra.  The heruka traces its origin to the same pre-Buddhist traditions of India as the dakini, in the retinues of wrathful Siva or Mahakala in which he served as terrifying demon.
Heruka literally means "blood-drinker," and in a tantric Buddhist setting this refers to drinking the blood of self-cherishing, doubt, and dualistic confusion.* The tantric interpretation of the term heruka derives a further meaning: his nature is beyond conventional cause and effect, existence, and duality. He is the ultimate expression of the radiantly selfless qualities of the mind.  Having drunk the blood, the heruka experiences bliss. He is fearlessly at home in the charnel ground, and under his gaze it is no longer merely charnel -- it is a palace.
"The heruka is depicted with nine classical moods (Kartap gu) which gives clues about his manifestation. He is said to be charming, with dazzling ornaments; brave, posing and strutting; threatening, with rolling eyes and a wrathful grimace; laughing, a raucous "ha ha"; fierce, with laughter that mocks, "hi, hi, hum, phat"; fearsome, grinding his teeth and brandishing a weapon; compassionate; with bloodshot eyes and radiant skin; outrageous, with gaping mouth and clicking tongue; and peaceful, gently gazing at the tip of his nose.** The heruka embodies the mountain-like presence of the enlightened masculine principle in Vajrayana Buddhism, with its range of fierce, hearty, and gentle qualities."

They also mention some of the Attributes of Wrathful Deities:

Some of the attributes (symbolic implements) wielded by Dharmapalas such as Mahakala and other wrathful manifestations can include:
Sword (T. rtse-mdun, Skt. khadga) symbolizes the wisdom, knowledge or ability to cut through delusion or obstacles.
Flags, standards and banners (Skt. dhvaja) which represent the victory of Buddhist teaching over delusion.
An elephant goad or ankh (Skt. ankusa) for taming desires.
Spears (T. mdun) that fix or pin down.
Hammer (Skt. mudgara) mace or club (Skt. gada) that crush opposition.
Bow (Skt. ripa) and arrows (Skt. sara):  action at a distance.
Vajra staff (Skt. vajradanda)
Trident (T. rtse-gsum, Skt. trishula) symbolizing the Three Jewels.
Lasso (Skt. pasa) that constrains negative forces.

Lastly, here is an interesting short-text on "Peaceful and Wrathful Forms" and a link to a another question-site where a being has asked about wrathful deities. You might find some answers here too. Hope this helps. This was a very good question. I didn't know about this and have now learned a lot researching the topic.

To add to the other answers here, the wrathful Buddhas are often seen as protectors. Mahākāla for instance is just another form of Avalokiteśvara. He (mahakala) is considered the tantric "watchdog", protecting those that appropriately practice Vajrayana, but is said to turn quickly on those that misuse those teachings.
Another well known wrathful diety is Vajrapani

According to the Pancavimsatisahasrika and Astasahasrika Prajnaparamita any Bodhisattva on the path to Buddhahood is eligible for Vajrapani's protection, making them invincible to any attacks "by either men or ghosts".

He is part of a trio with Manjushri and Avalokiteśvara. They represent power, wisdom, and compassion of the Buddhas.
In the bardo the first set of deities you encounter are the peaceful ones.
Later you encounter the wrathful ones.
If one realizes that both are projections on ones own mind, and does not fear and embraces the energy involved it is said one can reach liberation in the in-between state in this way.
The worst thing one can do is to fight or flee from them, these energies are not avoidable and are due to past karma/kamma. Just as when the "mirror" that reflects your last life might show you things that make you uncomfortable, to deny your bad deeds at this time magnifies the karma.
One important thing to note about these wrathful deities is that they are not devils, they are not like Mara. They are there for practitioners benefit and protection.
The peaceful and wrathful deities have a mantra as well called the 100 diety mantra.

Om Ah Hung Bodhi Chitta Maha Sukha Jhana Dhatu Ah Om Rulu Rulu Hung Jo Hung

To hear Tibetan pronunciation you can go here
More information about it here


text:
Is there a Buddhist term for a lack of self identity?
Is there a Buddhist term for a lack of self identity?
I don't (of course) mean a radical acceptance of the anatta doctrine, but whether the Buddha or any Buddhist scholar or writer, talks explicitly about being unable to take one's own personal identity seriously enough: even to the extent of becoming quite thirsty for one.
Thank you for your compassion :-)

I think the question is unclear. Could you elaborate on how this is different from Anatta? And the meaning of this sentence: "...being unable to take one's own personal identity seriously enough: even to the extent of becoming quite thirsty for one...". Thank you.

by self identity i mean who you think you are based on who you've been, not from moment to moment but day to day or year to year. by thirsty i just mean psychologically attached to the experience

Asking about "who you think you are based on who you've been, not from moment to moment but day to day or year to year" seems unclear and highly philosophical.

Is your term "self identity" maybe the same thing as the Buddhist term "identity view"? There's a not-very-good question but several answers, which describe what identity view is, at What are examples of identity-view?

@SriLanka it's a standard psychological concept

@ChrisW i don't think it's identity view, but when i've edited the question you're free to say otherwise :)

You posted a link to "Self-concept" as an explanation of self-identity. Would it also makes sense to edit the text of the question and the title, to ask about "self concept" instead of "self identity": is the "standard psychological concept" of "self concept" what you want to ask about? Also you're asking about a lack. So might you have a hyperlink to a description of "lack of self concept"? Is "lack of self concept" also a standard psychological concept, is it said to have symptoms, etc.?

My model of development is: Pre-Ego (child, animal), Ego, Neo (self with ego not operating), Nondual (no self), and whatever comes beyond that. So, in my view, getting beyond Self is natural, inevitable (if the person develops) and should be common. But people get stuck in their Ego stage. I have only met one other person who really understood what it means to be a Neo (something like recurring, ongoing Satori), but I see it around me all the time. Perhaps this is what you are talking about? Also: Nonduality is now being studied in the research on Persistent Nonsymbolic Awareness (PNSE).

Rats! PNSE should say Persistent Nonsymbolic Experience. (Can't edit my comment now).

To study the Way is to study the self.  To study the self is to forget the self.  To forget the self is to be enlightened by all things.~Dogen

I think the question is asking about a self-identity in the Right Livelihood sense: making a living in the world doing something that aligns with your personality and idiosyncratic proclivities.
Am I right OP?

If I understand this question, this might be a diffuse perception of the skhandas, as these are the groupings that might better translate as the identity constructs (in the modern sense).
In that case, i'm not sure there is a word or discussion of identity disorders (if that is what you're referring to) -- i've never seeing this being discussed in any text.
I have seen (modern) people talk about supposed risks of mindfulness meditation for people with specific mental disorders who already have difficulties with making sense and perceiving or associating (or too inclined to disassociate) certain things. But whether these are real risks of what specific practice and to whom exactly i'm not sure (e.g. some researchers do advocate mindfulness meditation to people with specific identity disorders). This is the closest link to buddhism and this lack of self identity i've heard of.


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What is meant by "possessed by spirits" in Buddhism?
In this answer there is a quote from The Buddhist Monastic Code 1 - The Patimokkha Rules Translated and Explained by Thanissaro Bhikkhu, which reads in part

only when one is possessed by non-human beings

In that book there are several references to being possessed by spirits or non-human beings, such as this from page 44.

State of mind. The bhikkhu must be in his right mind. Any statement he
  makes while insane, delirious with pain, or possessed by spirits does not count.

My question is, who or what is doing the possessing? Is there a belief in Buddhism that some being (a hungry ghost or something else?) would actually take over the mind of a human? Is that type of cross realm interaction possible?
How literally is possession by spirits to be understood? Thank you.

Not all literally I would say. It's a way of speaking about psychology.

Yes, various other beings can possess humans e.g. hungry ghosts, Yakṣas, Maras
Here's one occasion where a human was possessed by a Mara named Dusi and the Mara being Moggallana himself in that life.

At that time, Moggallana was Mara, chief of demons, lord of the lower
worlds, and his name was Mara Dusi. He had a sister by name of Kali
whose son was to become the Mara of our age. Hence Moggallana's own
nephew was now standing in front of him at the door post. While being
the Mara of that distant time, Moggallana had attacked a chief
disciple of the previous Buddha by taking possession of a boy and
making him throw a potsherd at the holy disciple's head so that blood
was flowing.
http://www.accesstoinsight.org/lib/authors/hecker/wheel263.html#ch9

Not only humans, even Brahmas can be possessed by Maras.

"Then Mara, the Evil One, taking possession of an attendant of the
Brahma assembly, said to me, 'If, good sir, this is what you discern,
if this is what you have awakened to, do not lead (lay) disciples or
those gone forth. Do not teach the Dhamma to (lay) disciples or those
gone forth. Do not yearn for (lay) disciples or those gone forth.
There were, good sir, before your time, brahmans & contemplatives in
the world who claimed to be worthy & rightly self-awakened. They led
(lay) disciples & those gone forth. They taught the Dhamma to (lay)
disciples & those gone forth. They yearned for (lay) disciples & those
gone forth. Having led (lay) disciples & those gone forth, having
taught the Dhamma to (lay) disciples & those gone forth, having
yearned for (lay) disciples & those gone forth, they — on the break-up
of the body, with the cutting off of life — were established in a
coarse body.
 Brahma-nimantanika Sutta: The Brahma Invitation

It's also said that Ananda wasn't able to invite Buddha to prolong his life during the last days of his life because he was possessed by Mara during that time. During the first council monks accused Ananda for not doing that and he defended himself by giving this excuse.

The fourth accusation which the monks leveled at Ananda, referred to
the time when he had neglected to beg the Blessed One to remain for an
aeon. Ananda defended himself by saying he had been possessed by Mara
at the time, and therefore had not been responsible for his actions —
how could he have otherwise failed to make this request?
http://www.accesstoinsight.org/lib/authors/hecker/wheel273.html#section-9

So, according to Buddhist texts such cross realm interactions is possible and it seems that the victim is not responsible for his or her actions done at that time.

But the victim suffers the karmic consequences of the actions done:
"Now, Evil One, on that occasion most of those human beings, when they died, reappeared on the dissolution of the body, after death, in a state of deprivation, in an unhappy destination, in perdition, even in hell." These are the householders possesed by Mara Dusi who scolded and reviled the bhikkus.

@UrsulRosu Where did you find this quote? Anyway it says 'most of these human beings', not everyone. So we can't really say it's due to the karmic consequence of those actions. Buddha said, "O! Bhikkhu monks, it is volition - cetana that I call Kamma, -cetanaham bhikkhave kammam vadami, having willed one acts through body - kaya kamma, speech - vaci kamma, or mind - mano kamma. " The victim had no will to do those kamma, so he shouldn't be getting the consequences.

This can be found in MN 50: "Then, when the Māra Dūsı̄ had taken
possession of the brahmin householders, they honoured, respected,
revered, and venerated the virtuous bhikkhus of good character. Now,
Evil One, on that occasion most of those human beings, when they
died, reappeared on the dissolution of the body, after death, in a
happy destination, even the heavenly world." So there is kammic consequence of action, even if possesed.

Only some went to hell/heaven because the consequences of kamma can be experienced in this life, in the next life, or in some future life.

And from Angulimala Sutta we know that what should he experience as thousands of years in hell, he experienced as a rock thrown in his head that made him bleed, so each experience kamma acording to his actions but also acording to how much virtue one has, like in the simile of the piece of salt thrown in a great river, and the piece of salt put in a small cup.

In my tradition, the Shambhala line of teachings by Chogyam Trungpa Rinpoche, ascending to Jamgon Kongtrul and ultimately Milarepa, the "spiritual" and the "material" phenomena are understood to be two narrative explanations of the same underlying reality. So when we talk about supernatural stuff like spirits etc. we always refer to phenomena that actually happen in everyday life but lack adequate representation in the mainstream narrative.
In modern language, spirits are semi-stable configurations of information-causation that inhabit the noosphere and sustain themselves through behavioral patterns mediated by sentient beings.
To give an example you can relate to, you send your child to a summer camp and they come back intoxicated by the camp spirit. They act funny, and when you point it out, they say we don't get it and insist their gestures and attitude are their own, while you clearly see they've picked it up. After several days home the camp spirit rubs off.
...In the adult world there may be a spirit of organization that influences all employees in certain ways etc...
Another example is campaign spirit - your teen daughter goes to a Greenpeace lecture and comes back possessed by the Greenpeace spirit. She donates her money to the ecological causes, spends her summer washing the birds caught in the oil spill etc.
If you look at it this way, you will see the world full of spirits, large and small. Your husband purchases a new camera, and feels obliged to spend his weekend taking pictures - he is possessed by the camera spirit.
These all seem harmless, until you remember all harm and violence incurred by religious and political fanatics - possessed by their respective spirits.
I don't know why late Theravada's Pratimoksha discounts misdeeds done while possessed by the spirits. From my perspective, guarding the doors of the senses is responsibility of the practitioner, and it is due to incorrectly applied attention that possession by spirit occurs. In the highly competitive world, where we are constantly bombarded by ads, campaigns and other forms of spirits, we must be very selective when it comes to which ones we give our attention to. As said in that Native American folktale, whichever wolf we feed is getting stronger. So is with spirits.
We can let ourselves be driven by spirits that correlate with greed, hatred, and confused values -- or we can feed useful spirits, conducive to health, peace, harmony, and informed, educated, strategic attitudes.
Buddhism itself can be seen as a spirit, and as any spirit can only take us this far until we become its pawns. So in the advanced stages of Vajrayana practice, our game becomes to liberate ourselves from the spirit of Buddhism, just like we've worked to come out of influence of worldly spirits. Once we are past that phase, having awakened (bodhi) from the spirit dream, we can use spirits as tools to pay our student dues forward and save the rest of sentient beings from the matrix into the real world.

Apparently, the foremost Dada poet in Japan was possessed by mara, and ended up in an ayslum.
Very intriuging, I think.

The Encyclopedia of Asian Philosophy associates this phenomenon with Zen sickness.

Mara will sometimes disturb or harm you when you are having certain good progress in meditation. You may hear some stories about people who become mentally ill after they practiced meditation for a long period time. This is one of the reasons.

After my 6 night stay in Brahma Vihara Arama temple in Bali I lost my mind and by Gods grace and power I didn’t end up in psychic asylum… that was the worst experience in my life. I was under the influence of a very powerful demonic entity.


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Does any sect claim that only Shakyamuni will ever achieve great nirvana
ARe there any schools which say that Shakyamuni the historical Buddha, alone, will ever be a Buddha?
I understand that some might identify him fully with the dharmakaya, but isn't it completely canonical that there is a Buddha vehicle for others, at some point in time?

No, there are no schools that claim this. All the schools accept that there were previous Buddhas before Buddha Shakyamuni and that there will be Buddhas after him as well.

do you have any source for this

You can't really give a specific citation to show that all schools don't believe in something. All you can do is point to them all and indicate that none of them do, and all the major scriptural collections (i.e. the Pali Canon accepted by the Theravada school, the Chinese Canon accepted in East Asia, and the Tibetan Kangyur) of all the major schools have references to previous and future Buddhas.

I realize that. I just find it odd that there WOULDN'T be some small, one-off branch of Buddhism that believes just this. Which is why I'm asking for a source that has led you to believe that such a branch doesn't exist, to make such a claim that NO schools claim this. How do you know that NO schools claim this?

It is something so basic and fundamental to the teaching of both Theravada Buddhism and Mahayana Buddhism that if such a group existed, it would definitely be mentioned in general sources. By definition, Mahayana Buddhism is about teaching people how to become fully enlightened Buddhas, and within the Theravada school, the very early Suttas mention the previous Buddha Kassapa. Without proof that such a group DOES exist, we have to default to assuming they don't.

So you don't know this to be true, then. You're assuming. Thank you for the clarification.


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How can the sensations of the meditation object (attention to the breath) be made more noticeable?
While practicing sitting vipassana meditation, using the felt sensations of the abdomen rising and falling with each breath as the meditation object, there is the frequent flood of mental images arising and passing away. The mental images seem much stronger, i.e. more noticeable, than the felt sensations of the meditation object. Is there a mind or mindfulness technique to make the felt sensations more noticeable, thus improving concentration on the chosen meditation object?

Related questions: (1) Loosing awareness, (2) Overcoming distractions in meditation as per the Tripitaka? and (3) Overwhelming thoughts - Mindfulness and awareness

Being mindful of the rise and fall of the abdomen is what you do when other phenomena are not occurring. If you are seeing mental images, note "seeing...seeing...." When the images fade, return to the rise and fall of the abdomen.
From Venerable Yuttadhammo's booklet, How to Meditate, A Beginner's Guide to Peace:

It is this rising and falling motion that we will use as our
  first object of meditation. Once we are able to observe the
  motion of the abdomen without difficulty, it will serve as a
  default object of meditation for us to return to at any time.

and:

In regards to feelings, when a sensation arises in the
  body, one should fix one's attention on it, discarding the
  abdomen and focusing on the sensation. If a feeling of
  pain should arise, for example, one should take the pain
  itself as a meditation object.
Any one of the four foundations may serve as a
  meditation object, as all four are aspects of reality. It isn't
  necessary to stay with the rising and falling of the
  abdomen at all times.

From Practical Vipassana Meditation Exercises by the Mahasi Sayadaw:

In short, whatever thought or reflection occurs should be noted. If you imagine, note as 'imagining'. If you think, 'thinking'. If you plan, 'planning'. If you perceive, 'perceiving'. If you reflect, 'reflecting'. If you feel happy, 'happy'. If you feel bored, bored. If you feel glad, 'glad'. If you feel disheartened, 'disheartened'. Noting all these acts of consciousness is called cittānupassanā.
Because we fail to note these acts of consciousness, we tend to identify them with a person or individual. We tend to think that it is 'I' Who is imagining, thinking, planning, knowing (or perceiving). We think that there is a person who from childhood onwards has been living and thinking. Actually, no such person exists. There are instead only these continuing and successive acts of consciousness. That is why we have to note these acts of consciousness and know them for what they are. That is why we have to note each and every act of consciousness as it arises. When so noted, it tends to disappear. We then go back to noting the rising and falling of the abdomen.

So just note "seeing...seeing..." with your mental images until they fade away then go back to the rising and falling.

The mental images seem much stronger, i.e. more noticeable, than the felt sensations of the meditation object.

If it's hard to direct the mind to attend to something, if it's easily seduced and distracted by anything other than the object you want to give attention to, this means samadhi is lacking. This is what gives one the ability to develop a unified mind (one pointedness), resting it on an observed object without distractions; "applied and sustained thought". So, it might come in hand to train samatha as well.

@Ryan and Thiago Silva - thx for replies. I tend to agree on needing some Samantha training. I find myself vacillating between trying to use a vipassana approach and a samantha approach. I know I need greater concentration skills, and I also want to be faithful to the vipassana approach. Often times the spurious mental images seem to be coming and going too quickly to get any focus on them, at which time I just try to refocus on the very faint breath object. Nevertheless, everyone's replies are very appreciated.

Is there a mind or mindfulness technique to make the feeling sensations more noticeable, thus improving concentration on the chosen meditation object?

Yes there is! Being mindful of whatever arises, i.e. mental images, clearly noting their arising and ceasing, will strengthen your mindfulness and concentration.
The point of vipassana is to come to see the impermanent, unsatisfying, and uncontrollable nature of all phenomenon, and here, my friend, you have it! The goal is not to maintain concentration on one object of your choosing.
edit: I'm assuming you're practicing vipassana? If this is the case, please edit and add the vipassana tag, as that would change the appropriate answer to the question

thx. Edits done. However, still curious if there is a way to enhance the awareness of the felt sensations, which occasionally  seems faint relative to the awareness of the mental images. It can be difficult to "catch" the transition of awareness from the felt sensations to the awareness of the mental images. Is this condition simply weak concentration? Thx for the reply!

this is weak mindfulness. just keep practicing properly, noting properly, and maintaining equanimity in your practice, and it will improve with time. in this way you will come to enhance your awareness of the arising of sensations.

it should also be noted that there is nothing wrong with having weak mindfulness, nor should you be practicing with the sole intent to change this experience. you should approach this equanimously, and continue to practice simply noting, unbiased towards the experiences that arise. simply know that "this is the way it is".

Shucks! ... was really hoping for a magic bullet :-P ... back to the grind stone :) thx _/|_

no shortcuts here friend :)

Mental factors has Sensations associated with them. So any metal activity will have a Sensation. You have Perceived association with each Sensation. So one Sensation brings up associated memories or fantasies, which create more Sensation which continuously bring up more such thoughts. This is how Metal Proliferation happens which is a Verbal Fabrication. To remove the Verbal Fabrication you have to cut out Thinking and Pondering by with Sustained and Applied Effort to Direct Your Mind to the meditation object with the Intention, Continuous Reviewing to ensure your focus is on the object. (Also see my answer https://buddhism.stackexchange.com/a/12342/295 for further details.)


text:
Clenching teeth and pressing tongue against roof of mouth
This may sound similar to this question, but it's not the same.
This practice appears to be similar to the Khecari Mudra of Hindu yoga, but it's not the same, because the tongue need not be inserted into the nasal cavity. It is sufficient if it is pressed against the roof of the mouth.
This is based on the quote below from the Vitakkasanthana Sutta.
My questions are:

Since this appears in the Pali Canon, do contemporary Theravada teachers teach this?
How does it work? Does it stimulate certain nerves?
Is this considered a last resort to controlling the mind, or is it a regular part of Buddhist practice?

"If evil, unskillful thoughts — imbued with desire, aversion or
  delusion — still arise in the monk while he is attending to the
  relaxing of thought-fabrication with regard to those thoughts, then —
  with his teeth clenched and his tongue pressed against the roof of his mouth — he should beat down, constrain, and crush his mind with
  his awareness. As — with his teeth clenched and his tongue pressed
  against the roof of his mouth — he is beating down, constraining, and
  crushing his mind with his awareness, those evil, unskillful thoughts
  are abandoned and subside. With their abandoning, he steadies his mind
  right within, settles it, unifies it, and concentrates it. Just as a
  strong man, seizing a weaker man by the head or the throat or the
  shoulders, would beat him down, constrain, and crush him; in the same
  way, if evil, unskillful thoughts — imbued with desire, aversion or
  delusion — still arise in the monk while he is attending to the
  relaxing of thought-fabrication with regard to those thoughts, then —
  with his teeth clenched and his tongue pressed against the roof of his
  mouth — he should beat down, constrain, and crush his mind with his
  awareness. As — with his teeth clenched and his tongue pressed against
  the roof of his mouth — he is beating down, constraining, and crushing
  his mind with his awareness, those evil, unskillful thoughts are
  abandoned and subside. With their abandoning, he steadies his mind
  right within, settles it, unifies it, and concentrates it.

This happened a lot to me spontaneously the first year I began meditating - my tongue would press hard against the roof of my mouth, my neck would rock back and forth and my body would twist into yogic asanas etc. Even now my neck regularly locks with my sternum in a jalandhara bandha when in concentration. These processes are well described in hatha yoga but they are part of being human, existing since the dawn of man. Patanjali merely documented it pretty well. Nothing magical or special about it, unless one also considers breathing in and out magical.

Buddho has shared important reminder of natural manifestations of correct cultivation... across entire religions. The passage that questioner shared though really to me suggests a way to invoke Right Effort when all else fails--not the natural, proper creative manifestation when residing in emptiness.

In Mahayana, we take such things as expression devices - not literal instructions. In this case clenched teeth are a pointer to great effort, great application of willpower.
The objectives of samatha are to disidentify from the mind, to learn to control attention, to acquire concentration/willpower, to integrate the disjointed layers of psyche, and generally to attain a "tamed", "pliable" mind.
It is towards these that we apply the great effort. Especially when the inappropriate thoughts arise, and if other techniques did not work (such as switching attention to antidotes and other techniques described in that sutra), as a last resort, we apply the sheer willpower.

According to Thich Nhat Hanh's "The Heart of the Buddha's Teachings" this is a mistake in transmission:
page 13-15 on google books.
In reality he was asking us not to do this!
The book quotes the Mahasaccaka Sutta, which contains a passage in which the Buddha said that he tried this technique unsuccessfully.

Even during the Buddha's lifetime, there were people such as the monk Arittha, who misunderstood the Buddha's teachings and conveyed them incorrectly (see the Arittha sutta). It is also apparent that some of the monks who memorized the sutras over the centuries did not understand their deepest meaning, or at the very least, they forgot or changed some words. As a result, some of the Buddha's teachings were distorted even before they were written down. Before the Buddha attained full realization of the path, for example, he tried various methods to suppress his mind, and they did not work. In one discourse (the Mahasaccaka Sutta), he recounted:

I thought, Why don't I grit my teeth, press my tongue against my palate, and use my mind to repress my mind?
    Then, as a wrestler might take hold of the head or the shoulders of someone weaker than he, and, in order to restrain and coerce that person, he has to hold him down constantly without letting go for a moment, so I gritted my teeth, pressed my tongue against my palate, and used my mind to suppress my mind.
    As I did this, I was bathed in sweat.
    Although I was not lacking in strength, although I maintained mindfulness and did not fall from mindfulness, my body and my mind were not at peace, and I was exhausted by these efforts, This practice caused other feelings of pain to arise in me besides the pain associated with the austerities, and I was not able to tame my mind.

Obviously the Buddha was telling us not to practice in this way.
  Yet this passage was later inserted into other discourses to convey exactly the opposite meaning:

Just as a wrestler ... use his mind to defeat his mind.

Often we need to study several discourses and compare them in order to understand which is the true teaching of the Buddha.

In the version of the Maha-Saccaka Sutta on Access to insight, the quoted paragraph is a bit different. It ends with "But the painful feeling that arose in this way did not invade my mind or remain" instead of "I was not able to tame my mind", which seems to change the meaning again!

How does it work? Does it stimulate certain nerves?

As Ahmed wrote, it is taught in Tai Chi.
When my Tai Chi teacher taught and explained it, it was in terms of Chi flow. His English vocabulary was small and I don't understand Chinese at all, so he could only give a partial verbal explanation. If I recall correctly though, a fairly constant theme of his was that our Chi tends to be too high in our bodies (e.g. up in our heads), and that we should practice bringing it lower (e.g. to centre it around the dan tien).
Some people (e.g. some Westerners) dispute whether there even is such a thing as Chi, calling it a "pre-scientific" description etc. Asking "How does it work, physically?" might not get satisfactory answers.
For me it might work as a learned compliance technique. Because I practised it (literally 'practice' i.e. deliberately repeating the same 'form' on many occasions), pressing my tongue to the roof of my mouth triggers many associated awarenesses (i.e. thoughts, movements, body-memories); it's a mnemonic which starts a whole check-list, for example, "head up, chin back, shoulders down, back straight, pelvis forward, knees bent, and connect the direction (in or out) of the breath to the direction (pull or push) of the hands". So for me it's (at least) a trigger of learned reflexes.
Similarly, perhaps if (or assuming that) you have practised that way (with the tongue) then using your tongue will trigger a remembered state from your past practice.
For what it's worth, it's a convenient gesture: like putting the palms of your hands together, or touching a thumb to a finger tip, it's almost always available, something that you can do in a moment, whether or not you're sitting down.
It's also a constant physical/sensory reminder: if you do it then you feel it, so it's a feedback loop or a circuit. If your mind would otherwise wander maybe it gives you something to focus your attention on.
The gesture also blocks your mouth. Maybe (I'm guessing) that helps to prevent not only talking but even subvocalizing (of internal monologue), and maybe turn awareness towards breathing.
Maybe too (I don't know, maybe I'm reading the wrong thing into it), in the context of the passage quoted in the OP, maybe it's that even if ever you don't control the arising of "evil, unskillful thoughts" you can at least continue by controlling your tongue and so on i.e. controlling your physical form.

that's the word, subvocalizing!

Yes I have heard this, was taught by a Theravada teacher in Sri Lanka.
I am not sure how it works, in fact I cannot explain in neurological terms. However I know serotonin helps to go back to the thing we want to do, to concentrate on. Serotonin can be increased by physical activity, I do not whether pressing tongue does that, but there must be a mechanism behind. According to the sutta, this method is the last resort to be used when a distraction comes to mind when the practitioner attends to a particular or useful theme.

Having the tongue pressed against the roof is standard practice through all traditions. This is basic meditation advice, part of 9-step preparation for meditation, because of the way the chi channels connect, this is good for one's health and growth.
Clenching one's teeth on the other hand I have only read in the suttas as a "last resort" in eliminating and resisting distractions/temptations.
It should be taken as a literary device expressing the Buddha's compassion for our suffering and his urging for us to head straight to what we seek, rather than be side-tracked.

What is your reference for the statement that this is standard practice through all traditions?

Many meditation manuals. One being "Only a Great Rain"

A manual is simply one person's take on the canonical texts. I know Suzuki mentions this in "Zen Mind, Beginner's Mind." But how much of this is simply being passed down without thought? I see the same thing happen in martial arts schools. "Why do we do it this way?" "Because, that's how I was taught."

You asked for a reference, i gave it to you which by the way is a collection of actual buddhist trainings unlike zen mind.. Which is just commentary on buddhist  trainings. Check that book out and then also check out some taoist works to verify the empirical claim about how this affects chi channels.

‘Suppose, with my teeth clenched and my tongue pressed against my palate, I beat down, hold back,
  and crush the mind with mind.’
So, with my teeth clenched and my tongue pressed against my palate, I beat down, held back,
  crushed the mind with mind. While I did so, sweat ran from my armpits.
It was just as if a strong man, holding a weaker man by the head or shoulders, were to restrain,
  subdue, and attack him;
even so, with my teeth clenched and my tongue pressed against my palate, I beat down, held
  back, and crushed the mind with mind, and sweat ran down my armpits.
But although I exerted tireless energy, and unremitting mindfulness was established in me, my
  body was overstrained and lacking calm, because I was exhausted by the painful striving.
But, Aggivessana, such painful feeling that arose in me did not invade my mind and remain.

Mahā Saccaka Sutta
The above description mentions this as practice to gain unremitting mindfulness but did not achieve its goral. Also this is associated the period of self mortification of the Bodhisattva. When it is generally mentioned in the context of Vitakka Saṇṭhāna Sutta it is recommended as a last resort where all else fail and with a word of caution citing that it was what was used during the harsh ascetic practices.
So to answer you questions. Yes. It is recommended with a strong word of caution. It is not recommended for prolonged practice.
It speculated that since in Anapanasati meditation around the mouth is used and in this case upper pallet is used since there is some significance in this region perhaps due to nerve centers or other reasons. But the Suttas are silent on the exact reason.