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What is the difference between an arhat, bodhisattva and a buddha?
What is the difference between an arhat, a bodhisattva and a buddha? References to the scriptures would be most helpful.
I'm open to both Theravada and Mahayana perspectives.

According to the Prasangika-Madhyamika Mahayana school of Tenets,
A Hinayana arhat abandoned afflictive obscurations by way of realizing emptiness, but has not abandoned knowledge obscuration. He as achieved abiding nirvana. Therefore, although they are free from the conception of true existence, and from true suffering, they are not free from the imprints of ignorance (i.e. knowledge obscurations). We say that it is like removing garlic from a container: the smell will still be there. So, because they still have the imprints of ignorance, (1) they are not free from the appearance of true existence, and (2) they are reborn with a mental body, due to the imprints of ignorance (in our case, we are reborn to due karma and afflictions).
In his commentary to Maitreya’s Sublime Continuum: The Essence of a One Gone Thus, Gyaltsab Je says:

For the Hearer and Solitary Realizer arhat, because they do not meditate on the perfection of wisdom.
  It means that although Sravaka and Pratyekabuddha arhats cultivated the wisdom realizing emptiness, their wisdom is not conjoined with bodhicitta. Therefore, it is not a perfection of wisdom.

Commenting Gyaltsab Je, Geshe Jamphel Gyaltsen said:

Bodhisattvas, hearers (shravakas) and solitary realizers (pratyeka buddhas) arhats do have realizations of reality, but they do not realize it in the same way as a buddha.

And:

The Hinayana arhats and bodhisattvas on the three pure grounds, are reborn due to uncontaminated karma that propels them to take birth and their body is a called a mental body.

A bodhisattva is a person who generated effortless bodhicitta (the wish to achieve enlightenment for the sake of all sentient beings). Since effortless bodhicitta is the entry gate to the Mahayana path, he entered the Mahayana small path of accumulation. When he cultivates wisdom, it is conjoined with emptiness and that makes his mind vast (due to bodhicitta) and profound (due to realizing emptiness). He wishes not to abide in individual liberation (abiding nirvana) but to be free from the extreme of peace (abiding nirvana) as well as from samsara. Therefore, he wishes to achieve non-abiding nirvana, which is the attainment of a buddha.
We say that in terms of wisdom, a Hinayana arhat is more powerful than a bodhisattva before the 8th bhumi, because he abandoned afflictive obscurations while the bodhisattva abandons them from the 8th ground.
Geshe Jamphel Gyaltsen said:

Having generated spontaneous bodhicitta the bodhisattva has entered the Mahayana path [the path of accumulation] and the cause is great compassion, the concern for all sentient beings. He blocks the two extremes in two ways.

The Lam Rim, Shantideva’s Bodhisattvacharyāvatāra, Asanga's Bodhisattvabhumi,  and Maitreya’s Ornament for Clear Realization  explain well what bodhicitta is, how it is the entry gate to the Mahayana, etc.

A Buddha abandoned both afflictive and knowledge obscuration, having generated the path perfection of wisdom (the wisdom of emptiness conjoined with bodhicitta). In his continuum, wisdom and bodhicitta are the same mind: the omniscient mind of a buddha that realizes all objects of knowledge directly, past present and future, in an unmistaken way, etc. He achieved non-abiding nirvana, abiding neither in samsara nor in individual liberation. His enlightened activities are uninterrupted.
Maitreya’s Sublime Continuum explains the two bodies of a buddha that can also be divided into three, four, or five.

this is great, but consider using a different term instead of Hinayana as I know some take this as a perjorative. I know you did not intend it that way at all, but it might be good to use a different term to prevent any misundertanding @TenzinDorje

Arhat - a person who has achieved Nirvana. The Buddha is a Arhat too, there are disciples who learn the Dhamma as Buddha has taught, who become Arhats too.
Buddha - on who achieves Nirvana without a teacher.
Bodhisatta - One who aspires to be a Buddha

I thought about your answer and I believe you are coming from the Theravada tradition, which I'm unfamiliar. So, bodhisattva is merely a word to describe someone on the path to buddhahood? How does this reconcile with the Mahayana conception of Bodhisattva as someone who has already achieved enlightenment and aspires the enlightenment of other sentient beings? How do the Scriptures use the word 'bodhisattva'?

Bodhisattva is someone in the path to Buddhahood. Aspires enlightenment for oneself and other beings also.

Does the Arhat aspire enlightenment for others too?

Yes. Some but they have to learn the teaching from a Buddha.

What is the difference between an arhat, bodhisattva and a buddha?

It's not easy to give an explicit answer, the rather thorough one is here. An Arhat must be a Bhikkhu living a monastic life but a Bodhisattva is not necessary. The goal for the Arhat path aspires to conquer the afflictions of mind thus sever the cord of Samsara and dwell in Nirvana, the Bodhisattva path is in dealing with the afflictions acquired the wisdom (Bodhi) thus returned again and again to Samsara cultivating merits and wisdom by ferrying others from the sea of suffering, the Samsara.
The Bodhisattva path has detailed grades of advancement, main categorization is from the 1st grade to the 10th:

...佛告觀自
  在菩薩曰。善男子。成就大義得未曾得出世間心生大歡喜。是故最初名極喜地。遠離
  一切微細犯戒。是故第二名離垢地。由彼所得三摩地及聞持陀羅尼。能為無量智光依
  止。是故第三名發光地。由彼所得菩提分法。燒諸煩惱智如火焰。是故第四名焰慧地
  。由即於彼菩提分法方便修習。最極艱難方得自在。是故第五名極難勝地。現前觀察
  諸行流轉。又於無相多修作意方現在前。是故第六名現前地。能遠證入無缺無間無相
  作意。與清淨地共相隣接。是故第七名遠行地。由於無相得無功用。於諸相中不為現
  行煩惱所動是故第八名不動地。於一切種說法自在。獲得無罪廣大智慧。是故第九名
  善慧地。麁重之身廣如虛空。法身圓滿譬如大雲皆能遍覆。是故第十名法雲地。... 《解深密經》

The article in earlier link said the 7th grade is equivalent to an Arhat in terms of Liberation (解脫), from 8th grade onward a Bodhisattva has acquired wisdom and ability beyond an Arhat does. The article is said to be written by ven. 聖嚴法師 it should be a trusted source.
In addition the 8th grade Bodhisattva is able to cite his own version of Dharani (Mantra) (which I believe is the Ultimate Knowledge of sound), and will never ever stumble from The Path until attained Buddha-hood for he has seen the Ultimate Reality.
A Buddha is the 11th grade - so to speak:

...永斷
  最極微細煩惱及所知障無著無礙。於一切種所知境界現正等覺。故第十一說名佛地... 《解深密經》

Now the "body" for an Arhat, a Pratyeka-buddha and Tathagata the Buddha are also different:

...佛告曼殊室利菩薩曰。善男子。若於諸地波羅蜜多。善修出離轉依成滿。是名如
  來法身之相。當知此相二因緣故。不可思議無戲論故。無所為故。而諸眾生計著戲論
  有所為故。世尊。聲聞獨覺所得轉依。名法身不。善男子。不名法身。世尊。當名何身。善
  男子。名解脫身。由解脫身故說一切聲聞獨覺。與諸如來平等平等。由法身故說有差
  別。如來法身有差別故。無量功德最勝差別。算數譬喻所不能及... 《解深密經》

Namely, Tathagata the Buddha has the Dharma-body (法身), but Arhat and Pratyeka-buddha has Liberation-body (解脫身), not Dharma-body. I think it's like comparing a cloth with stain removed (Liberation-body) to a cloth that's spotless (法身).
And there are detail explanations about how the "body" of the Tathagata-buddha is different from and capable of doing, in 《解深密經》.

Thanks for the link. I'm more familiar with Chinese Mahayana Buddhism, so your answer would resonate with me more. However, I feel there is a lack of scriptural references. I would like to see, for example, the consistency between 解深密經 and the Sutta/Abhidhamma Pitaka. I upvoted your answer, though.

By "Sutta/Abhidhamma Pitaka" do you mean the Pali Canon? Unfortunately I don't read Pali and the English translated work available online is not in my priority of study at this moment. I won't be able to provide further info in this context for the time being.

Your answer here: https://buddhism.stackexchange.com/questions/20489/sounds-during-meditation/20529#20529 is a good answer. Why did you delete it? Thanks

"contemplating the body in the body..." can be translated & thought about in different ways. You should start a question/thread about it. Thank you for your posts here. I will read them in detail at a later time. Regards

@Dhammadhatu Appreciate the inquiry. Good answer chooses right audience... (abridged).


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Can a person without any of the five physical senses attain arhatship?
I have read a person without senses cannot attain arhatship or even go through the noble eight fold path. But the story of Chakkupala thero confuses me somewhat

I think it's been said that beings in the formless realms cannot attain enlightenment because they cannot perceive (hear, read, or otherwise learn) the Buddha's Dharma ... perhaps too they also can't perceive the three characteristics of existence.
This says,

The inhabitants of these realms are possessed entirely of mind. Having no physical body, they are unable to hear Dhamma teachings.

See also footnote 8 on this page,

An Abhidhamma text, the Vibhanga — drawing on a passage in DN 1 — mentions another level of devas of form not listed here: the Non-percipient beings, a level in which there is no perception at all. The commentary explains that they are not listed here because this attainment is open to hermits and seers outside the Buddha's teaching, and does not require virtue. This, however, ignores the fact that the four jhanas and four formless states are also open to people outside the Buddha's teaching; and although virtue helps with the attainment of jhana, it is nowhere stated in the Canon that the jhanas cannot be attained by a person whose virtue is not pure. A more likely reason for omitting the Non-percipient beings here is that this state, unlike the jhanas and four formless states, is not conducive to the arising of insight, and so would not be considered a desirable goal.

I don't know how to reconcile the above two statements, i.e. whether formless is the same as non-percipient.

People who are blind or deaf, or who are blind and deaf can learn to communicate. So I suppose this is only applicable to non-percipient beings in the formless realms: not people.
Cakkhupala Thera was able to hear the dharma.

“Avuso, how many conditions are there from which right view arises?”
“Avuso, right view arises from 2 conditions, that is: the voice of another and wise attention.
These, avuso, are the 2 conditions from which right view arises.”

Mahā Vedalla Sutta
So to develop right view in the Noble 8 Fold Path you need to be in a realm where you can learn the Dhamma.
If you achieve some stage of sainthood before being born in a formless realm though you do not have senses, you can progress to full enlightenment. I.e., when you have the 1st glimpse of Nirvana the path factors are established to progress unaided or further guidance, even in realms where you cannot find guidance.
You empirical understanding should be that validating the teaching. Only a Full or Private Buddha can understand the experiential result of meditation without guidance. Any disciple will need some guidance to interpret the experience hence this process is: Pariyatti (theory), Patipatti (practice), Pativedha (empirical validation). It is the theory you learn that is getting validated at least at intermediate stages. This is why you need to learn it from another (kalyāṇa-mittatā), i.e., learn from a Buddha or a Disciple. You need your sense faculties to learn.
In case of Chakkupala, blindness was not an impediment to learn, practice and empirically validate. In the story, the Ven. Sir practiced hard, with proper guidance and finally realised the teaching. Also one essential aspect of the practice is wise attention would have been present.

A person without the five physical senses is still having the Vijnanas (識) of the five senses. A human is attributed with the five senses, 吾 is a Chinese character of I/me/myself, it's formed with upper a 5 (五), lower a mouth/opening (口). The formation of the five senses are with 3 factors: sense-Consciousness (識), sense-Organ (根), sense-Object (塵). A human born blind, deaf, dumb... whether born with defect or later damages, the five sense-Consciousnesses are always intact. What damaged are the sense-Organs, not the Vijnanas. Vijnanas cannot be destroyed, not even death. Hence a deceased person is still able to see, hear, smell... even with more acute and powerful capacity. Apart from the five senses, there is another additional, the mind/thinking organ, the 6th sense, called 意根. Therefore,

Can a person without any of the five physical senses attain arhatship?

the answer is yes.

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Is there an established monastic order, with the beleifs and practices same as the Goenka school of meditation?
Let me clarify,what I want to know is
(a) 'An established monastic order' - This the Goenka school is not.
(b) With principles and beleifs and aims as close to the Goenka school as possible?

(a) 'An established monastic order' - This the Goenka school is not.

There is no Goenka School. Generally this is referred as the linage of Saya Gyi U Ba Khin and Ledi Sayadaw U Ñanadhaja. Also it is influenced by Webu Sayadaw
Ledi Sayadaw U Ñanadhaja and Webu Sayadaw are Buddhist monks. Also there many teachers who are Buddhist Monks who are particle according to S. N. Goenka.

(b) With principles and beliefs and aims as close to the Goenka school as possible?

Many of the references in the disclosure are meticulously referenced from the Tipitaka. So any monastic order which practices which is close to the Tipitaka would share the same beliefs.

Thanks. Of course they would share the same beleifs, but do they actually carry out such practices ?

Goenka teachers what U Ba Khin taught which is a based on Ven. Ledi Sayadaw linage and Ven. Webu Sayadaw.

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Citta Vithi in Abhidhamma
There is a chapter under citta vithi in Abhidhammattha Sangaha. In which of the seven books in Abhidhamma this concept appear?

Hi and welcome to Buddhism SE. We also have a Guide and a Resource section for new users that you might like

As you mentioned, Chapter IV of the Sangaha describes citta vithi. The Visuddhimagga includes many partial references (look under "cognitive series" in the index) but no complete analysis. Clearly, the material in the Sangaha is a later development of what is found in the Visuddhimagga (perhaps 500 years earlier). The material in the Visuddhimagga is a later development of sporadic references found in the Patthana (Conditional Relations). For example, on page 72 of PTS Conditional Relations Vol II, it says, "advertance (avajjana) is related to five-fold consciousness through proximity condition". On page 74, it says, "Life-continuum (bhavanga) without applied thought but with sustained thought is related to advertance by proximity condition." Proximity condition (and contiguity condition) imply a process. In summary, the fully-worked-out version found in the Sangaha was developed from fragments found in the Visuddhimagga (and commentaries) and these were developed from even earlier (and much more primitive) fragments found in the Patthana.

Vīthi is paṭṭhāna of abihdhamma-pitaka and the whole commentary, that were learned from buddha by sāriputta-mahāsāvaka then he author them in his phrase.
You must memorize paṭṭhāna in pali and learn it with the tipitaka memorizer, to prove that it is Vīthi.
If you doubt about  abhidhamma's and commentary's history, please read this question:
https://buddhism.stackexchange.com/questions/21226/what-are-timeframe-were-pali-canons-included-commentaries-done-especially-mah

This is first found in the Visuddhimagga.
You should understand the difference between Sutta Abhidhamma vs Abhidhammatha Sanga ha.
https://discourse.suttacentral.net/t/sutta-abhidhamma-vs-abhidhammatha-sanga-ha/4725

I assume the OP understands the difference. There's a chapter in the Sanghaha (i.e. in the commentary): and so it is in the commentary ... but the question isn't about the commentary (nor about the Visuddhimagga): the question is, in which of the seven books of the Abhidhamma is it found? It's presumably a topic of the Abhidhamma Piṭaka, otherwise it wouldn't also be in the commentary.

The way I understand it is not in the Sutta Abhidhamma. I may be wrong.

You find it in a compendium of the cognitive process chapter 4. of Abhidhammatha Sanga ha file:///C:/Users/Sarath/Downloads/Comprehensive%20Manual%20of%20Abhidhamma%20(3).pdf

This question came up in a Dhamma discussion which I was part of but I am not sure or have verified if this is valid.
Citta Vithi and Javana are found in the Abhidhamma Commentaries but not in the Abhidhamma Pitaka. I.e., it does not appear in the any of the 7 books.

Vīthi is paṭṭhāna of abihdhamma-pitaka and the whole commentary, that were learned from buddha by sāriputta-mahāsāvaka then he author them in his phrase.
You must memorize paṭṭhāna in pali and learn it with the tipitaka memorizer, to prove that it is Vīthi.
If you doubt about  abhidhamma's and commentary's history, please read this question:
https://buddhism.stackexchange.com/questions/21226/what-are-timeframe-were-pali-canons-included-commentaries-done-especially-mah

In the same way what are the references to the concept of cuti patisandhi citta; ie. patisandhi citta conditioned by cuti citta in a minute fraction of a second.  Is it also mentioned in pattana?. This is so important that by describing the mechanism of cuti patisandhi in this way only, the main teaching of that 'there is no sole' can be justified.

Vīthi is paṭṭhāna of abihdhamma-pitaka and the whole commentary, that were learned from buddha by sāriputta-mahāsāvaka then he author them in his phrase.
You must memorize paṭṭhāna in pali and learn it with the tipitaka memorizer, to prove that it is Vīthi.
If you doubt about  abhidhamma's and commentary's history, please read this question:
What are timeframe were pali canons, included commentaries, done, especially Mahavihara-Theravada?


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What is fruition in Buddhism?
I see it everywhere in my book on jhana. but don't truly understand it's meaning or even find a definition.

And path. The two are often mentioned together, and I'm still not completely sure what they each mean.

@DeusIIXII, this is an important question that you asked. I am going to be hard pressed for time, the coming three months. But I cannot ignore when a good question is asked. So I will expand on the earlier answer given. Do give me some time to formulate an answer.

Fruition is more related to the stages of Attainment. These levels of attainment are described as including four or eight kinds of individuals. There are four [groups of noble disciples] when path and fruit are taken as pairs, and eight groups of individuals, when each path and fruit are taken separately:

•  (1) the path to stream-entry; (2) the fruition of stream-entry;
  •   (3) the path to once-returning; (4) the fruition of once-returning;
  •   (5) the path to non-returning; (6) the fruition of non-returning;
  •   (7) the path to arahantship; (8) the fruition of arahantship.

So, Fruition simply means “Coming to Fruition”. It is the moment of the fruition of their path (magga-phala) – be it the stream-entry path, the once-returning path, the non-returning path, or the path to arahantship.
The moment of fruition is the understood experience and results in a turned-around vision of existence. The new understanding at the culmination of the stream-entry path recognises and go beyond the first three fetters (saŋyojana) that bind a being to rebirth, namely self-view (sakkāya-ditthi), clinging to rites and rituals (sīlabbata-parāmāsa), and skeptical indecision (Vicikicca).
The new understanding at the coming to fruition of the Sakadāgāmi or "once-returner," stage is first three fetters (saŋyojana) are fully cut off and that s/he has  significantly weakened the fourth and fifth saŋyojana.
The new understanding at the coming to fruition of the anāgāmi or "non-returning" stage is that s/he is free from Kāma-rāga (Sensuous craving) and Vyāpāda (ill will).
A key principle in Buddha Dhamma is cause and effect; nothing happens without a cause or a reason. The word “FRUITION” can be used here in this way: Even if root causes are there, we can stop them from bringing their results by blocking the conditions for them to come to FRUITION (a seed has the potential to bring about a tree, but for that to happen the seed must be given a fertile soil, water, and sunlight). In the same way, kamma vipaka (result of a past kamma) can come to FRUITION only when right conditions for the corresponding kamma seed to germinate are realized.  This is why we can prevent many bad kamma vipaka from come to FRUITION by acting with yoniso manasikara or by “being mindful” in seeing life through the ‘Dhamma Eye”.

Fruition is more related to the 4 stages of sainthood. This is realising of the fruit (Pala) of practice. What his means is you realized the path.

But, Suminda, the two concepts are often mentioned together -- path and fruition -- suggesting that the latter is more than just realizing the former, no? I mean, can one have path without fruition, or fruition without path?

They happen very closely. This is why they are mentioned together. But path happens 1st followed by fruition.

Thank you kind sir.. Once again you have helped me a lot.

You are welcome.

As the venerable appearing as @Saptha Visuddhi has given a detailed answer, I will give a simple one. Fruition is a significant milestone in the practice of Dhamma. The final fruit is the Arhathhood which is the elimination of suffering. A dhamma practitioner practices all the components of the Eightfold noble path, which includes development of wisdom until he/she reaches each of the 4 fruitions and finally the Arhanthood (or Buddhahood).

It is said that at each fruition, a taste of nibbana can be experienced. And once that it's experienced, a normal person would no longer have doubt about the Buddha, Dhamma or Sangha. And that person is bound for nibbana. The practice of vipassana removes mental defilements step by step, increasing wisdom, until a person achieves each of these states.

Once one achieved stream-entry, one will know what is what. The same applied to once returner, non-returner etc. In layman term to make clear, if one go to a retreat home/dwelling, the entrance to the dwelling is the path(magga) and the dwelling where one(stream-enterer) stay is fruition(phala). But magga is very very short just like passing by the entrance while phala is the stage where one (stream-enterer or once returner or non-returner or arahant) can be in this stage for long enough depend on the concentration achieved just like dwelling in a retreat home. If pre-determined before meditation session, can stay in the specific fruition stage for a definite period of time.

Eradicating all craving and realizing nibbäna


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Is it possible to adhere to the practices and beliefs of both Buddhist and Christianity?
What are the similarities and contrasts between Buddhism and Christianity? To what extent do they make it possible (or not) to practice in and hold the beliefs of both?

Have you have looked at other topics tagged [tag:christianity]? And are you asking about any/all forms of Buddhism (and of Christianity), or are you asking about any specific school?

I'm tempted to close this question as "too broad".

Also, given that this is a Buddhism.SE site, the main point of [tag:comparative-religion] topics is to clarify Buddhism (e.g. by contrasting it with Christianity, to help people who know more about Christianity than they do about Buddhism). So questions ought to be phrased such that they ask more about Buddhism than they do about Christianity. This question seems symmetric (50% Buddhism and 50% Christianity) and thus is not really on-topic. Beware that many users of this site know less about Christianity, and you may get inexpert answers if the question asks too much about Christianity.

@ChrisW Also, the question title and question body are really completely different questions... It's also a duplicate of other questions.

The question is interesting. For a person to be Christian, should Christianity accept them? for it to accept them, should they be following or should they be not doing certain things? Should this question not be asked in Christianity SE instead? I don't think Buddhism puts any restrictions as such.

@ChrisW it's fine, how is it too broad?

@Uuu There's more than one school of Buddhism (e.g. Theravada versus Shin), more than one school of Christianity (e.g. Roman Catholic versus Quaker); and IMO there are innumerable similarities and differences. Even a single one of these innumerable topics (i.e. "faith") was the subject of entire answers in "What are the differences/similarities in the concept of faith as used in Buddhism and Christianity?".

If the question were only the title i.e. "is it possible to be both?", then the answer might be more simply "Yes", combined with references to some individuals who are accepted as both.

@ChrisW Come  on, please don't do that.

As @ChrisW has already stated, just with different words: there should surely already be a statement of a christian authority as well as of some buddhist authority that this is legally possible or not. For the deeper, more spiritual question, of whether this makes sense, there should be a myriad of positions (my favorite teacher, Thich Nhat Hanh for instance, thinks this is compatible, the german Theravada-scholar Hans Gruber thinks it is not compatible) So: if you want a discussion - this BSE is not the intended place, if you want a canonical answer, there should be links...

I'm new enough to make mistakes in how to ask questions, and while I hope the question isn't closed I would bow to the group wisdom but hope there is a way to retrieve the data in closed questions if that happens.

I've edited the question to reflect the fact that it's being interpreted in terms of practicalities, rather than legalities. Feel free to revert to the original if I've overstepped.

@ChrisW There are plenty of questions that never refer to a specific schools and you let them stay on. In a way, Christianity is another tradition of Buddhism.  We're is written this golden agenda you have for this sight? You never told me about it if there is but I don't mind alienation.  I think you should just leave this question alone. I think everyone's got they're claws out for no good reason. Does anyone really think that the way we do mass decision making now with the little dictatorship on top here in a forum about truth is just the thing to do?

and it's impossible that this forums decision making process is corrupted, right?,  because we say, we can't be corrupted because we are us, right? We are just trying to do the right thing, by judging people so we can edit them out and make this forum better, right? Well, we often don't do the right thing because we are defiled!!! Remember? Somebody has to judge others? Do they? No they don't. If we value this forum above our friends what kind of forum do we have?

@Uuu Andrei once expressed the opinion that, "A good question has an incline, so its answers naturally turn out good. A bad question is inclined toward flamewars, and takes extra effort and wisdom to answer well." If you want to discuss this further, please use this meta-topic to do that.

@ChrisW Well beam us over there then :)  what's a flamewar? Look, people are going to have ideas and opinions about Buddhism until the end of time.  You think the democratic process will reveal the best answers?  There must be more enlightened people than I thought, huh?

Take a look at the Maria Kanon Zen Center. It might have content that's of interest to you: http://www.mkzc.org/

I know three Buddhists who consider themselves also Taoists and Christians. It's a matter of how we interpret and understand these teachings. It is quite easy to interpret them to be three expressions of the same message. But this would not be the Romanised Christianity of the priests and the masses.

Similarities between Buddhism and Christianity:

The word 'birth' has a psychological meaning (rather than a physical meaning), as Jesus explained to Nicodemus in John 3 and the Buddha explained in SN 12.2; SN 23.2 & SN 5.10. Therefore, 're-birth' happens when living rather than at the termination of life. MN 86 states:

Sister, since I was born in the noble birth, I do not recall intentionally killing a living being.

Jesus replied, “Very truly I tell you, no one can see the kingdom of God unless they are born again.” “How can someone be born when they
  are old?” Nicodemus asked. “Surely they cannot enter a second time
  into their mother’s womb to be born!”  Jesus answered, “Very truly I
  tell you, no one can enter the kingdom of God unless they are born of
  water and the Spirit.  Flesh gives birth to flesh, but the Spirit
  gives birth to spirit. You should not be surprised at my saying, ‘You
  must be born again.’ (John 3)

The word 'death' has a psychological/spiritual meaning (rather than a physical meaning).

Dhammapada 21. Heedfulness is the path to the Deathless. Heedlessness is the path to death. The heedful die not. The heedless are as if dead
  already

Dependent origination is taught in both, namely, James 1:15:

But each one is tempted when by his own evil desires he is lured away and enticed. Then after desire has conceived, it gives birth to sin;
  and when sin is fully grown, it gives birth to death.

While the Gospels mostly teach about 'Eternal Life', which is alien to Buddhism, at times Christianity teaches about the 'Deathless', which is the same as Buddhism, such as in the Gospel of Thomas verse 1 and John 21:23.

And he said, "Whoever discovers the interpretation of these sayings will not taste death."

Because of this, the rumor spread among the brothers that this disciple would not die.

Craving ('tanha'; lit. 'thirst') as the cause of suffering is taught in both; as is the end of craving being 'Nibbana' or 'Eternal Life'.

What causes conflicts and quarrels among you? Don’t they come from the passions at war within you? James 4:1

But whoever drinks the water I give him will never thirst. Indeed, the water I give him will become in him a fount of water springing up
  to eternal life. John 4:14

'The world' ('loka') is equated to suffering & the 'lokuttara' state of 'beyond the world' is the state of freedom.

John 16:33 - The world will make you suffer. But be brave! I have defeated the world!"

John 18:36 Jesus said, "My kingdom is not of this world".

1 Corinthians 7:29-31 What I mean, brothers and sisters, is that the time is short. From now on those who have wives should live as if they
  do not;  those who mourn, as if they did not; those who are happy, as
  if they were not; those who buy something, as if it were not theirs to
  keep;  those who use the things of the world, as if not engrossed in
  them. For this world in its present form is passing away

Insofar as it disintegrates, monk, it is called the 'world.' SN 35.82

Dhammapada 167. Follow not the vulgar way; live not in heedlessness; hold not false views; linger not long in worldly existence.

Titus 2:12 It teaches us to say “No” to ungodliness and worldly passions, and to live self-controlled, upright and godly lives in this
  present age....

'Satan' is the ruler of the world:

The time for judging this world has come, when Satan, the ruler of this world, will be cast out.
John 12:31

44. Who shall overcome this earth, this realm of Yama and this sphere of men and gods? Who shall bring to perfection the well-taught path of
  wisdom as an expert garland-maker would his floral design?
45. A striver-on-the path shall overcome this earth, this realm of Yama and this sphere of men and gods. The striver-on-the-path shall
  bring to perfection the well-taught path of wisdom, as an expert
  garland-maker would his floral design.
46. Realizing that this body is like froth, penetrating its mirage-like nature, and plucking out Mara's flower-tipped arrows of
  sensuality, go beyond sight of the King of Death!
Dhammapada

Both teach the destruction of kamma.

And what is the cessation of kamma? From the cessation of contact is the cessation of kamma; and just this noble eightfold path — right
  view, right resolve, right speech, right action, right livelihood,
  right effort, right mindfulness, right concentration — is the path of
  practice leading to the cessation of kamma. AN 6.63

Galatians 2:16 - Nevertheless knowing that a man is not justified by the works of the Law but through faith in Christ Jesus, even we have
  believed in Christ Jesus, that we may be justified by faith in Christ,
  and not by the works of the Law; since by the works of the Law shall
  no flesh be justified.

Both have a Trinity or Triple Gem. Buddha reveals/makes known the Dhamma (Truth & Nibbana), the path to which is represented by the Sangha, who live the Holy Way of Life (Brahmacariyaṃ). Jesus reveals/makes known the Father, of which the Holy Spirit is the way. Both teach a disciple may attain the same realisation as the teacher.

So this holy life, bhikkhus... it is this unshakeable deliverance of mind that
  is the goal of this holy life, its heartwood, and its end.”
MN 29

John 14:26 But the Advocate, the Holy Spirit, whom the Father will send in my name, will teach you all things and will remind you of
  everything I have said to you.

Hasten to be saved without being urged! Instead, be eager of your own accord, and, if possible, arrive even before me; for thus the Father
  will love you. The Apocryphon of James

Both teach the practise of mental purity & energetic watchfulness.

Matthew 25 At that time the kingdom of heaven will be like ten virgins who took their lamps and went out to meet the bridegroom. Five
  of them were foolish and five were wise. The foolish ones took their
  lamps but did not take any oil with them. The wise ones, however, took
  oil in jars along with their lamps. The bridegroom was a long time in
  coming, and they all became drowsy and fell asleep.... Therefore keep
  watch, because you do not know the day or the hour.

Both teach 'god is love'. The Brahmans, like the Jews, believed they were Brahma's (God's) chosen people. But Buddha in the Tevijja Sutta taught the Brahmans god is love, i.e., the path to union with Brahma is to radiate boundless love towards all beings. Similarly, Christianity teaches god is love (1 John 4:8), which was contrary to Judaism, in which god was jealous, violent & tribal.

And he lets his mind pervade one quarter of the world with thoughts of Love, and so the second, and so the third, and so the fourth. And
  thus the whole wide world, above, below, around, and everywhere, does
  he continue to pervade with heart of Love, far-reaching, grown great,
  and beyond measure. Just, Vāseṭṭha, as a mighty trumpeter makes
  himself heard—and that without difficulty—in all the four directions;
  even so of all things that have shape or life, there is not one that
  he passes by or leaves aside, but regards them all with mind set free,
  and deep-felt love. Verily this, Vāseṭṭha, is the way to a state of
  union with Brahmā. Tevijja Sutta

Beloved, let us love one another, because love comes from God. Everyone who loves has been born of God and knows God. 8Whoever does
  not love does not know God, because God is love. 1 John 4:8

In summary, based on many similar core concepts, which use very similar terms, Christianity appeared to be an attempt to transpose Buddhism onto a theist framework; which was fatally flawed because it is impossible to transpose transcendent Nibbanic Buddhism onto worldly creationist Kabbalah Judaism.

It is not possible to be both a Buddhist and a Christian because Buddhism teaches all things without exception are 'anatta' ('not-self') & 'the elements' ('dhatu') as its core & fundamental principle; where as Christianity includes 'self' in the form of Christ & The Father as a core principle.
In other words, Buddhism is strictly 'impersonal' where as Christianity is 'personal', where salvation is based on a personal relationship between the 'small-self' & a personal god (Christ & The Father).
For example, Matthew 16:25 states:

Whoever loses his life for My sake will find it.

Luke 23:42 states:

Then he said, “Jesus, remember me when You come into Your kingdom!” And Jesus said to him, “Truly I tell you, today you will be with Me in
  Paradise.”…

Buddhism explains there are many types of liberation/salvation of mind (MN 43), which include liberation via loving-kindness & liberation via emptiness of self, the later being the foremost & unshakeable.

He keeps pervading above, below & all around, everywhere & in every respect the all-encompassing world with an awareness imbued with good
  will (loving-kindness): abundant, expansive, immeasurable, free from hostility, free
  from ill will... This is called the immeasurable mind-release.
And what is the emptiness mind-release? There is the case where a monk, having gone into the wilderness, to the root of a tree, or
  into an empty dwelling, considers this: 'This is empty of self or of
  anything pertaining to self.'
Now, to the extent that there is immeasurable mind-release, the unprovoked mind-release is declared the foremost. And this
  unprovoked mind-release is empty of passion, empty of aversion,
  empty of delusion.
MN 43

Christianity is merely liberation via loving-kindness where as Buddhism is liberation via emptiness of self.

Also, Christianity teaches salvation is 'Eternal Life' where as Buddhism teaches salvation is 'dispassion' that occurs via the realisation of impermanence & not-self. In other words, Christianity is a doctrine of 'Eternalism' (the belief a self exists after death), which is a wrong view in Buddhism; where as Buddhism is a doctrine of impermanence.

In its most esoteric interpretation (which is rejected by most Christians), Christianity is 'mysticism' where as Buddhism is 'straightforward'.
Jesus said he taught using parables to hide teachings & the New Testament is replete with the language of metaphor, which results in most Christians being unable to discern between the literal & metaphorical.
Where as the Buddha taught straightforwardly & plainly, with key terms explicitly defined.

Also, Christianity is fatally connected to the Old Testament of Judaism, which allows killing in many circumstances, such as war & heresy. This is why Christianity has had many Inquisitions.

In conclusion, Buddhism states it is "impossible" for a person of right view to take refuge in another teacher, thus it is not possible to be both a Buddhist and a Christian.
Since Buddhism states: "‘It is impossible, it cannot happen that two Accomplished Ones, Fully Enlightened Ones, could arise contemporaneously in one world-system", the view of Buddhism is those teachings of Jesus that are similar to Buddhism have their source in Buddhism. Therefore, the Buddha is the teacher & Jesus is the student.

He understands: ‘It is impossible, it cannot happen that a person possessing right view could acknowledge another teacher ― there is no
  such possibility.’ And he understands: ‘It is possible that an
  ordinary person might acknowledge another teacher ― there is such a
  possibility.’
He understands: ‘It is impossible, it cannot happen that two Accomplished Ones, Fully Enlightened Ones, could arise
  contemporaneously in one world-system ― there is no such possibility.’
  And he understands: ‘It is possible that one Accomplished One, a Fully
  Enlightened One, might arise in one world-system ― there is such a
  possibility.
MN 115

What you say is true if we are talking about standard modern Christianity  but Christ taught The Dhamma...today's Christianity often is the exact opposite from Christ's true Dhamma teachings. It's not taught in the same way but it is true Dhamma. Trust me on this one.

Uuu, since Thomas asked his question today, and not back when Christ was teaching, presumably he, Thomas, is referring to what you call "standard modern Christianity". Given that, it sounds kinda sensible that Dhammadhatu would use the same meanings as Thomas did, no? Equivocation is  a problem we should all avoid, yes?

@Uuu OK. I wrote another answer about similarities.

I think it is possible to be both anything, as long as you are open and prepared for your definitions of both Buddhist and Christian to change and evolve with time.
If you are stuck in place, then that would not work, even for someone who is "just" Buddhist.
In my experience it is kind of a useless pursuit to find "similarities" between religions. Let's just try to find ways to be good people ... and let the teachings sink in.

The answer depends on exactly what one means by Buddhism and Christianity since whether we like it or not those things are not precisely defined by anything like a universal authority. Even within each concept, there are huge differences. One could equally well ask if one can follow both Theravada and Mahayana, or both Catholicism and Protestantism.
That said, if we look at the most common uses of the two terms, the most simple, absolutely basic underlying definitions, applicable to lay-folk, might be something like this:

Buddhist: someone who accepts the Four Noble Truths, and is attempting to follow the Noble Eightfold Path so as to attain freedom from suffering and Nirvana. We could maybe add something about taking the three refuges and adhering to the five precepts, but those muddy this discussion I think
Christian: someone who accepts Jesus Christ as their personal Lord and Savior, him being the only source of salvation and without whose intervention one will, after death, suffer eternal torment and separation from God. We could maybe add something about having been baptized, and being willing and able to say "Jesus Christ is Lord" (cf. 1 Cor 12:13), but again I think those just confuse things needlessly.

Given those really basic definitions, and assuming we take them more or less literally (very important; see later) there is simply no way to pursue both approaches. Absolutely front and center of Christianity is the dude Jesus, his death and alleged resurrection, the fact that those constitute atonement for sin, and so on. You cannot be a Christian without regularly getting down on your hands and knees, literally or metaphorically, and worshipping Jesus. Accepting Him, being saved from sin, etc, and absolutely not meditation and resulting insight into the three marks of existence, etc, are what count.
And that is in stark contrast with Buddhism where Jesus doesn't really come into it, and breaking delusion etc are vital. Of course I can't see a problem with a Buddhist believing, just as Muslims do, that Jesus was a spectacularly important and awesome guy. But even if so, that's all he was, and as I said that's not remotely enough for a Christian.
HOWEVER... (there's always a however...)
All of that -- and it's pretty mainline exposition; I didn't make it up -- is only clearly the case if one takes those definitions literally. In particular it's if one interprets the meanings of the various terms in the context of contemporary scientific naturalism (sometimes manifesting as scientism) and essentially discards metaphysics (by which I mean the formal, philosophical type, as opposed to New Age fluffy stuff) or even modern philosophical systems such as phenomenology. With the much more sophisticated conceptual structures that those systems of thought provide, then the question as to exactly what Christianity or Buddhism (or many others) mean by any give concept needs more thought and so has more scope for compatibility.
I reckon that anyone with any degree of openness of mind, and willing to put in the work, cannot fail to see potential connections between what we got from the Buddha, Nagarjuna, Dogen, the neo-Platonists like Plotinus, scholastics like Aquinas, and so on, all the way to the present day.
So given all of that, I'll balance my earlier answer of "simply no way" with an alternative which is, "You're just going to have to try it out and see" :-) And to back that up, I'll offer two quotes (my italic emphasis in both):

From Christianity: "Therefore, my dear friends, as you have always obeyed--not only in my presence, but now much more in my absence--continue to work out your salvation with fear and trembling", Phil 2:12
From Buddhism: "Behold now, bhikkhus, I exhort you: All compounded things are subject to vanish. Strive with earnestness!" DN 16 PTS: D ii 72 chapters 1-6

I am both Buddhist and Christian. This is all just my opinion that follows.
The differences are mere interpretation. Jesus, seems to have been an acetic who spoke that he is God and the son of God and that just means he was one with God or enlightened in some way, I don't really know but it seems this way to me... based on my experience and what I know, bla,bla,bla and so forth.
The reason "Faith" is a big teaching is because a teacher often teaches a student about Faith so they can just know that the path they, the disciples are on, is true without having to intellectualise the teaching away with materialistic doubts. The parables were meant as ascetic teachings not worldly teachings for the family. Jesus was against family when it crushes spiritual progress. Family often is the source of a serious truth seekers encouragement to follow the herd and not be so serious.

As far as I'm concerned you can be whatever you like. You can even create your own religion if you so desire. Orthodox Buddhists and Christians will of course disagree but frankly I don't really care. The Buddha was not Buddhist and Jesus was not Christian. They were just enlightened beings and we all have that potential. Neither of them would have planned on their teachings becoming a massive worldwide cult and I'm pretty sure that if either of them knew what abhorrent acts have been and still are being carried out in their name they would be heartbroken. So follow what works and what resonates as truth for you. If it causes you and others to suffer less and find more peace and happiness stick with it, if not then ditch it. I don't subscribe to any one religion. I believe they all have nuggets of truth within them.

I think they are all sort of pointing at the same thing.

To what extent do they make it possible (or not) to practice in and hold the beliefs of both?

Buddhist practice revolves around the 3 trainings which is:

be moral and ethical
control your mind, impulses and emotions
understand and verify the reality of things at the experiential or empirical level

As most religions also must be preaching to be established in morality and ethics. Also no to be impulsive and do bad due to this. Also no religion can be against gaining wisdom.
Hence I think a Christian can practice Buddhism. Anyone practicing any religion can practice buddhism as I do not see any incompatibility.

Every religion worthy of the name calls on its followers to live a moral and ethical way of life, to attain mastery over the mind and to cultivate purity of heart. One tradition tells us, "Love thy neighbor"; another says, Salaam walekum - "May peace be with you"; still another says, Bhavatu sabbamangalam or Sarve bhavantu sukhinah - "May all beings be happy." Whether it is the Bible, the Koran or the Gita, the scriptures call for peace and amity.
...

S N Goenka addresses UN Peace Summit

I've noticed many things found primarily only in early Buddhism also appearing in NT Christianity this leads me to believe that Jesus encountered Greco-Buddhist monks or even that He himself was a Greco-Buddhist monk.
The earliest Buddhist scriptures are written in Gandhari which is from the Indo-Greek kingdoms. The earliest Buddhist statues were made in a Hellenistic Greek style and the NT is written in Greek...is it merely a coincidence?
They found Buddhist relics in Hellenistic Egypt and also certain Hellenistic Jews were rumored to have been Buddhists right before Christianity began.
There are certain concepts that appear primarily only in early Buddhism and not in Judaism that also appear in NT Christianity:

Hell
There is no hell in OT Bible or Judaism at all, only in the NT. Hell
is a central concept primarily in early Buddhism mentioned thousands
of times in Buddhist suttas seems to have originated in Buddhism but
does hell even exist in Christianity at all? Many Christian scholars
say there is no hell just mistranslations, others say a temporary
hell and still lots of confusion in between.
The Judeo-Christian idea seems to be that "God created the heaven and
the Earth" no hell, that everything is always good, nothing bad happens, and
everything always works in the end, it's always a happy ending so hell doesn't really make sense.
Whereas in Buddhism one of the Noble Truths is acknowledging that
pain and suffering exists so hell makes perfect sense
and fits in with Buddhism not with Judeo-Christian religions. There is no "Problem of Evil" in Buddhism.
According to The Buddha the majority of Christians and people in general go to hell, the animal realm, or the realm of ghosts after death. The majority of Christians seem to think of themselves a good person and that they would never go to hell or that it's really easy to go to heaven.
The "Evil One"
Mara the "Evil One" in Buddhism seems to be nearly the exact same figure as the "Evil One" in the NT but where does such a concept originate from? Mara is a central concept in early Buddhism.
Miracles such as walking on water as if was land
It's highlighted in the media that Jesus performed the miracle of walking on water as if it was land but in reality such mentions of things originates in early Buddhism. In Buddhism it is mentioned as a common iddhi power but in Buddhism anyone who develops concentration including even evil unenlightened beings can perform such miracles so it is not really viewed as anything that special though mentioned hundreds of times. The Buddha and many of his disciples allegedly performed many such miracles commonly.
Confession, repentance
Monks and lay followers confessing sins and repenting is a central concept in early Buddhism, there are rules for confession for monks but where does such an idea come from in Christianity?
Monks and nuns
Where does the concept of monks and nuns in early Christianity originate from? In early Buddhism there are all types of detailed rules for monks and nuns.
Church Bell/Temple bell Gong
Where does the Church bell idea come from? Seems very similar to the Buddhist temple bell.
God-man concept
The Buddha is one of the only teachers originally portrayed as a Supreme Being, fully enlightened, all-knowing in certain knowledges with many superhuman abilities.
Figures like Moses and Muhammad were just like ordinary people who never claimed to know anything with nothing special about them whereas Jesus was more like a God-man.
It seems like almost every God-man teacher came in post-Buddhist religions indicating that Buddhism originated such ideas.

So what's the explanation for these many concepts appearing in NT Christianity that are found primarily only in early Buddhism and not in Judaism? I see only two possibilities:

Just a big coincidence
Since early Buddhists were Hellenistic Greeks and the NT is written in Greek it some how came from early Buddhism (either by Jesus encountering Greco-Buddhist monks or even himself being a Greco-Buddhist monk)

The central basis of Jesus' teachings seems to be the practice of metta (loving-kindness) which is also recommended for Buddhists, except The Buddha gives more effective methods of surrounding your consciousness with loving-kindness rather than merely advising people to practice it. I'm sure many people want to be loving and kind but their unconscious impulses cause them not to be that's why there's the mind-exercises.
There are the 11 advantages of developing metta (loving-kindness) (AN 11.15):

You sleep well.
You wake happily.
You don’t have bad dreams.
Humans love you.
Non-humans love you.
Deities protect you.
You can’t be harmed by fire, poison, or weapons.
One’s mind gains concentration quickly.
One’s complexion is bright.
One dies unconfused.
If you don’t penetrate any higher, you’ll be reborn in a Brahmā realm.

So the practice of metta is in accordance with achieving arahantship but in Buddhism there's only two ways to escape suffering:

Gain birth in one of the Five Pure Abodes
Achieve arahantship

So Christianity is more compatible with lay followers of Buddhism rather than for those who desire to achieve enlightenment here and now.
The majority of Christians and people in general of all different faiths are most likely going to hell, the animal realm, or the realm of ghosts after death based on what The Buddha claims seems to be the natural state that people head towards the three lower destinations...Jesus' commandments and teachings were centered around the practice of metta but very few Christians seem to have faith or loving-kindness inside so it's going to be really unlikely that they go above the 3 lower destinations (hell, the animal realm, the realm of ghosts).
The Buddha claimed to be a sammasambuddha which means independently achieving enlightenment without the help of a teacher and also having the qualities of being a supreme teacher so it's expected that sammasambuddhas give rise to arahants, future paccekabuddhas, other religions and dhammas and we see so many things originating in early Buddhism appearing in post-Buddhist religions.
When sammasambuddhas appear they shock the entire universe-system, not only beings on Earth but even beings in heavenly worlds far above the Brahma realms.

Some people says that original teachings of Jesus is similar to Buddha's teachings. Thich Nhat Hanh's book "Living Buddha Living Christ" can be helpful for those who want to reconcile Christianity with Buddhism. Buddhism's methodology is to make people aware of what they are not instead of giving them direct explanations of the nature of the universe. So If Christianity is seen as a non-dualistic religion that also has meditation in it's teachings then people can remain Christians and go towards enlightenment perfectly with the help of the Buddhist teachings. You don't need to be a Buddhist to follow Buddhism's guidance in path of freedom from suffering.
In this answer you can see clearly that belief is certainly not essential in Buddhism:  https://buddhism.stackexchange.com/a/6/700
But If you see the "God" as a seperate entity that have rules and punishes people for their sins and sends them to heaven or hell for eternity, I think that it will be a very problematic thing to follow Buddhism's guidance while beliving in Christianity. The Sufis that lived in the past(not the modern Sufis) were obviously not following the original Islam but they somehow found the way to interpret Islam in such a way that they could go to freedom from suffering/Enlightenment perfectly. I think that Christians who want to apply Buddhist teachings in their daily lives don't need to do that because most likely the original teachings of Jesus was similar to the Buddha's teachings. But it is necessary to become free from the wrong perceptions(especially the seperate sky-god belief) while practising both of these religions.

Buddhism's ultimate truth is emptiness. Christianity's ultimate truth is God. In Buddhism, God is still in cyclic existence - will die and suffer again and again.

To practice most of what is taught in Dhamma, one does not have to be a Christian or Buddhist.  For example, there is no need to be a Buddhist or Christian when purifying the mind of defilements, which is key to meditation. Then there is no such thing as Christian or Muslim or Buddhist morality. Morality is universal and comes out naturally on the basis of benevolence, compassion, and wisdom having precedence over greed, hate, and ignorance.
In “Waking Up: A Guide to Spirituality Without Religion” (2014), Sam Harris has this to say:

“Spirituality must be distinguished from religion – because of people of every faith, and of none, have had the same sorts of spiritual experiences….Nothing that a Christian, a Muslim, and a Hindu can experience – self-transcending love, ecstasy, bliss, inner light – constitutes evidence in support of their traditional beliefs, because their beliefs are logically incompatible with one another. A deeper principle must be at work”.

Having said this, I have to say that where Buddhism and Christianity start to differ is when it comes to the Supra-mundane level. This is the lokottara - beyond this world of 31 realms – or the transcendental level of Dhamma. One can explain it intellectually but the reader will not get it, as it is in the practice that one gets to the supra-mundane levels of realization of such higher truths. So I will bring up just a couple of simple examples to show this.
The standard translation for sati—mindfulness—is probably derived from the passage in the Anglican Prayer Book that says, “Be
ever mindful of the needs of others.” In other words keep their needs in mind.
Even though the word “mindful” may come from Christianity, it’s the closest we
can get in English to what sati means in the Pali Canon. Sati in Dhamma is a “good” mental factor - “a good cetasika”.  “Sati” arises only in moral thoughts (kusala citta), and DOES NOT arise in akusala citta. “Good cetasika” do not arise in akusala citta (similarly, “bad cetasika” do not arise in kusala citta). Thus  “sati” is much more than “attention” or “mindfulness”. In a ‘Christian’ sense “sati” is the ability to remember or recall past events, but it is the “manasikara” cetasika that does that. When a person stops and contemplates whether an action one is about to take has moral or immoral consequences, and carries out only those actions that have moral consequences, then that person is acting with “sati” as per Dhamma.
In Buddhism the person acting with “sati” of a moral/ kusala citta as per Dhamma does it on ones own accord. In Christianity, the moral and ethical codes were created by Christ himself. The punishment for sinners was meted out by God, as well as by his earthly authorities. However, for those who are prepared to confess and repent for their sins, there is forgiveness, thus placing the relationship between God and Man on a personal basis. One who accepts this dictum / formal pronouncement from an authoritative source, can never be a Buddhist at a true or lokottara level.
It is through total submission to the Will of God that a Christian could ever hope for salvation. For a Buddhist the moral purity is just the beginning to the transcendental, and it is internalized within the mind of each individual and does not require the intervention of a divine external agency or force.  Here I should mention that the mundane versions of the PATH are followed by those ‘Buddhists’ who do not comprehend the Tilakkhana (anicca, dukkha, anatta). The mundane versions can be grasped by a normal human who is unaware of the true Tilakkhana or the true nature this world. The transcendental or lokottara versions can be comprehended only with an understanding of anicca, dukkha, anatta. Without an understanding of the anicca nature, we perceive that sense pleasures are good, and are worth striving for. But when one starts comprehending the anicca nature, one realizes that suffering is actually rooted in sense pleasures.
When one realizes that suffering is actually rooted in sense pleasures, then one is no longer a Christian. That is when s/he embraces the Dhamma, and as a Buddhist cultivates the transcendental 37 Factors of Enlightenment with the goal of attaining Nibbana, as s/he realizes that this world of 31 realms has nothing but suffering to offer in the long run.

You understand well at least intellectually , 'reality' when it is empty of our labels and borders.-Metta

In Buddhism, there are three kinds of defilements: greed, hatred & self-delusion. Christianity does not explicitly teach the self-delusion is a defilement and in fact teaches to transmute the 'self' onto the 'Jesus-self'. It states: "whoever loses his life for My sake will find it. Matthew 16:25". Also, Christianity states to give up greed/lust but does not really provide a clear & effective methodology. Only vipassana can uproot the defilements, which is why the Lord Buddha said the eightfold path is the ONLY PATH to purify the mind. Sam's experience of selflessness came by taking LSD.

Jesus said: “What comes out of a person is what defiles them. For it is from within, out of a person’s heart, that evil thoughts come—sexual immorality, theft, murder,  adultery, greed, malice, deceit, lewdness, envy, slander, arrogance and folly.  All these evils come from inside and defile a person.” The amount of defilements here is minor compared to Buddhism. Therefore, Christianity cannot purify the mind 100%.

I agree with what you've said. Now I've got to find some time to add a bit more to what I've posted, and touch on the aspect that you've pointed out. Thanks.

The 31 realms are all mental state of people (rather than other places). As for 'lokuttara' or 'beyond the world', this simply means to not cling to the world. Here, Jesus taught: "John 16:33 - The world will make you suffer. But be brave! I have defeated the world!" and "John 18:36 Jesus said, "My kingdom is not of this world". Therefore, the teaching of Jesus is 'lokuttara' however how to reach lokutara is not clearly explained by Jesus, except via forgiveness & non-judging.

More lokuttara: 1 Corinthians 7:29-31New International Version (NIV)
29 What I mean, brothers and sisters, is that the time is short. From now on those who have wives should live as if they do not; 30 those who mourn, as if they did not; those who are happy, as if they were not; those who buy something, as if it were not theirs to keep; 31 those who use the things of the world, as if not engrossed in them. For this world in its present form is passing away.

"Mindfulness" does not come from Christianity. Mindfulness or sati means "to remember" in Pali & Sankrit.

Practice of Buddhism requires refuge through proper understanding
Practice of Christianity requires refuge through proper faith
Former brings forth understanding that, after death, there is neither eternity (sasvatha) nor nothingness (uccheda). In that context, Christianity is uccheda. Hence there is a contradiction.
Latter beings forth a necessity for unwavering faith beyond reason in a supreme being. In that context, since practicing Buddhism requires a pragmatic view on self and what happens to one self, there is a problem following Buddhism while having a faith beyond reasoning in something or someone else.

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


text:
Thought arising
I often hear it being said that with meditation/mindfulness we observe the thoughts and feelings coming and going but I'm not sure if this is a clear explanation of what occurs because in my experience of practicing for over 6 years I don't think I have ever actually seen a thought arising. What happens with me is that I recognise that my mind is lost in a thought and once I do then the thought ends. This is different to noticing the arising. So I'm following breath, lost in thought, come back to breath, lost in thought etc. I can intentionally say to myself "ok now I'm going to think about ...." And in this way I can observe the process of thinking but unless I do this I don't see how its possible to see a random thought arising. Is this correct?   If this is not correct then why in 6 years can I still not do this?  The recognition of random thought is always in past tense.

It takes most people longer than 6 years, but keep at it, you will experience it eventually. Didn't the Buddha say it takes at least 7 years?

The presence of random thoughts make meditation impersonal, i.e., non / not self. You can realise you have no absolute control over thoughts. The nature of your flickering mind can also help you understand the 3 Characteristics.
When thoughts or other distractions arise (like pain), observe the sensation.

The meeting of the three is contact.
With contact as condition, there is feeling.
What one feels, one perceives.
What one perceives, one thinks about.
What one thinks about, one mentally proliferates.

Madhu,piṇḍika Sutta
Most proximate cause for thoughts to arise is perception. But what decides whether it is unwholesome or wholesome is feelings. So see thoughts arise be mindful of feeling and perception. Knowing these only will help you know what you are about to think about. Feelings will decide the wholesome / unwholesome root and perception will refine it with past experiences, memories, mental model to your intended action. Thinking about or thinking and pondering will lead to planning out the action in more detail.
Also:

(1) the latent tendency to lust reinforced by being attached to pleasant feelings;
(2) the latent tendency to aversion reinforced by rejecting painful feelings;
(3) the latent tendency to ignorance reinforced by ignoring neutral feelings.

Thinking lead to volitional activity and mental fool (Ahara). Also from feeling, Kamma arises:

... one generates that  formation, conditioned by which pleasure and pain arise internally

(Kamma,vāda) Bhumija Sutta
So once feeling arises you should try to stop this process leading to arising of the unwholesome roots, providing nutriment, arising of Kamma, leading to mental proliferation by being equanimous and noting impermanence. There are 2 paces which you can attack Dependent Origination, that is at ignorance and feeling. Knowing impermanence displaces ignorance and being equanimous stops feeling proliferating to craving and clinging.
If you were unable to stop when the feeling due to contact arises, when the volitional tough arises the respective feeling also arise in the body. This is a place where you can contemplate about moral constraint (Sila). Taking a step further you can constrain your thinking also, by contemplating the sensation it created and being equanimous towards it while seeing its impermanence, and perhaps neutralising one's perception by developing the opposite perception. [Indriya Bhāvanā Sutta] This you can use as a tool to prevent bad kamma (in account of feelings you should lessen unwholesome states and increase wholesome states - Kīta,giri Sutta):

Ananda, with ignorance as condition:
when there is the body, because of bodily volition, pleasure and pain arise internally;
when there is speech, because of verbal volition, pleasure and pain arise internally;
when there is the mind, because of mental volition, pleasure and pain arise internally.

(Kamma,vāda) Bhumija Sutta

Agitation and peace cannot co-exist. One way to achieve inner peace is Vipassana or insight meditation - a non-sectarian, scientific, results-oriented technique of self-observation and truth realization. Practice of this technique brings experiential understanding of how mind and body interact. Everytime negativity arises in the mind, such as hatred, it triggers unpleasant sensations within the body. Every time the mind generates selfless love, compassion and good will, the entire body is flooded with pleasant sensations. Practice of Vipassana also reveals that mental action precedes every physical and vocal action, determining whether that action will be wholesome or unwholesome. Mind matters most.

S N Goenka addresses UN Peace Summit
So when thoughts arise see that sensation is associated with it, knowing its impermanence thus ensuring it does not proliferate to unwholesome actions or further unwholesome thinking. Once you have realized the distracting thoughts, know the sensation associated with it and seeing its impermanence, finally return to the object of your meditation. In case it is breath meditation then return to the breaths. This is the most effective way to let go of distracting thoughts.
Also see: Sal,āyatana Vibhanga Sutta

I often hear it being said that with meditation/mindfulness we observe the thoughts and feelings coming and going but I'm not sure if
  this is a clear explanation of what occurs because in my experience of
  practicing for over 6 years I don't think I have ever actually seen a
  thought arising.

Yes. To clearly see a thought arising is a very advanced practise because it can really only occur clearly when the mind is strongly established in an empty concentrated mind.

What happens with me is that I recognise that my mind is lost in a thought and once I do then the thought ends.

Yes. This is a very honest & accurate appraisal of your practise.

Is this correct?

Yes. What you posted (in detail) is correct.
When the Buddha listed dhammas in various teachings, he generally did so from less advanced to most advanced. In AN 4.41, the Buddha listed 'knowing thoughts as they arise' after the practise of jhana. Whilst jhana is not necessarily a pre-requisite in all cases, to be perfect at 'knowing all thoughts as they arise' would require the development of jhana.
It is also important to understand that what is called 'cittanupassana' or 'contemplation of mind' is not related to thoughts and occurs when the mind has concentration (such as described in the Anapanasati Sutta, where 'contemplation of mind' is practised together with knowing each in-breath & each out-breath).
In other words, most Buddhists are fooling themselves when they believe they are successfully practising observing the mind. In your case, as I mentioned, your appraisal of your practise is not only honest but also accurate, in that you have the awareness to know you catch the thought after it has arisen rather than as it is arising.

What is a thought? In a Buddhist context thoughts (Citta) and thinking(Cétasika) are not the same.
(in context of thought as a noun, thought as in having thought and thinking thoughts)
Since it is important to proceed with knowing the difference, I will give an example I've learnt to clarify this. When you get angry, you can decide not to be angry and calm yourself down. Once the thought of anger came to you(Citta), if there was no way to act, i.e think (Cétasika) you won't be able to stop your anger
Next, citta and cétasika arise bound to one another, stay bound to one another and perish bound to one another. They occur only sequentially and in countless numbers per eye blink.

This ("they occur only sequentially and in countless numbers per eye blink") sounds like theory rather than practise. You personally obviously do not practise this but have only read this in a book. It follows it is not an answer to the question. Regards

@Dhammadhatu may I know where it is obvious that I do not practice this? The answer attempts to show that observing thoughts (Citta - Vinñana) has to be done using (Cétasika - Védana, Sangna, Sankhara). These subtle differences can be seen in "some" thoughts as you practice Sathara Sathipattanaya. A person who knows the theory also knows why it is hard to bind each thought to an observant cétasika "easily". May you realize the Four Noble Truths...


text:
Who or what is observing
I've heard it taught by various secular teachers that through mindfulness one can uncover the "true authentic self" because we realise that we are not thought but that we are awareness of thought. Please correct me if I'm mistaken but in my understanding this is not in alignment with Buddhist teachings and a misunderstanding of mindfulness.  We can discover that there is an awareness of thought, emotion etc but are we this awareness? Wouldn't Buddha say that even awareness is not self?  If we are not thought, not awareness, who or what is the observer? Is the observer just more impermanent phenomena?

This question might be already answered here: Is Mindfulness the same as having an Observer?

My thought about "true self" is that it just kicks the can down the road. What would the true self do, or be, or have, beyond what is available now? If I developed fully in to my true self, then what? True Nature, could mean something entirely different.

The mind observes. Consciousness observes. Awareness observes.

I've heard it taught by various secular teachers that through mindfulness one can uncover the "true authentic self"

No. Buddhism does not teach there is a "true authentic self".

because we realise that we are not thought but that we are awareness
  of thought.

No. Ultimately, there is no "we". Buddhism explains there are only five aggregates, namely:

Physical body
Feeling/sensation
Perception
Thinking/emotions
Sense consciousness

Please correct me if I'm mistaken but in my understanding this is not in alignment with Buddhist teachings and a misunderstanding of
  mindfulness.

Correct. What various secular teachers are teaching is not in alignment with Buddhist teachings.

We can discover that there is an awareness of thought, emotion etc
  but are we this awareness?

The mind discovers & the mind is aware. Consciousness knows thought, as follows:

Dependent on the intellect & ideas there arises consciousness at the intellect. The meeting of the three is contact.
If anyone were to say, 'The intellect is the self,' that wouldn't be tenable. The arising & falling away of the intellect are discerned.
  And when its arising & falling away are discerned, it would follow
  that 'My self arises & falls away.' That's why it wouldn't be tenable
  if anyone were to say, 'The intellect is the self.' So the intellect
  is not-self. If anyone were to say, 'Ideas are the self,' that
  wouldn't be tenable... Thus the intellect is not-self and ideas are
  not-self. If anyone were to say, 'Consciousness at the intellect is
  the self,' that wouldn't be tenable... Thus the intellect is not-self,
  ideas are not-self, consciousness at the intellect is not-self. If
  anyone were to say, 'Contact at the intellect is the self,' that
  wouldn't be tenable... Thus the intellect is not-self, ideas are
  not-self, consciousness at the intellect is not-self, contact at the
  intellect is not-self.
MN 148

'Consciousness, consciousness': Thus is it said. To what extent, friend, is it said to be 'consciousness'?
'It cognizes, it cognizes': Thus, friend, it is said to be 'consciousness.' And what does it cognize? It cognizes 'pleasant.' It
  cognizes 'painful.' It cognizes 'neither painful nor pleasant.' 'It
  cognizes, it cognizes': Thus it is said to be 'consciousness.'
Discernment (wisdom) & consciousness, friend: Are these qualities conjoined or disjoined? Is it possible, having separated them one from
  the other, to delineate the difference between them?
Discernment (wisdom) & consciousness are conjoined, friend, not disjoined. It's not possible, having separated them one from the other, to
  delineate the difference between them. For what one discerns, that one
  cognizes. What one cognizes, that one discerns. Therefore these
  qualities are conjoined, not disjoined, and it is not possible, having
  separated them one from another, to delineate the difference between
  them.
MN 43

Wouldn't Buddha say that even awareness is not self?

Yes.

If we are not thought, not awareness, who or what is the observer?

The mind is the observer; awareness is the observer; but "we" is not the observer.

Is the observer just more impermanent phenomena?

Yes. Refer to SN 12.61

It would be better for the uninstructed run-of-the-mill person to hold to the body composed of the four great elements, rather than the
  mind, as the self. Why is that? Because this body composed of the four
  great elements is seen standing for a year, two years, three, four,
  five, ten, twenty, thirty, forty, fifty, a hundred years or more. But
  what's called 'mind,' 'intellect' or 'consciousness' by day and by
  night arises as one thing and ceases as another. Just as a monkey,
  swinging through a forest wilderness, grabs a branch. Letting go of
  it, it grabs another branch. Letting go of that, it grabs another one.
  Letting go of that, it grabs another one. In the same way, what's
  called 'mind,' 'intellect' or 'consciousness' by day and by night
  arises as one thing and ceases as another.
SN 12.61

Maybe this is what she meant by: "There are no 'other people' "?

-1 Zen uses 'true self' and various synonyms extensively.

As I said in some posts sometimes can't avoid to offend some conventional Theravadists that their understanding of Anatta is incomplete/incorrect, worsen by bad(!) (sorry) Eng translated Suttas, @GavinSerra. It will lead to terrible future for human, it will be used by those who want to mold the world with their human hands sustaining only their own interests, literally.

for True Self believers, there is a Hindu forum here. Happy & safe travels.  https://hinduism.stackexchange.com/

@Dhammadhatu for Nihimsm believers there is also this forum: [link]https://philosophy.stackexchange.com/questions/tagged/nihilism. Leading the seeker of Buddha astray by incomplete understanding stated as if quoting from The Gospels (Suttas) the fruit is grim. All the best.

@Dhammadhatu With your inspiration I will move one of my questions [link]https://buddhism.stackexchange.com/questions/19098/can-cyborg-trans-human-reach-enlightenment-when-enlightenment-is-depended-on-a which received cold response in this forum to Nihilist forum, with edit, when I have time.

A being is made up of the 6 sense bases or the 5 aggregates and arise and an impersonal process governed by Dependent Origination. Notion of self is both a view and perception in beings who have not realised reality as it is.
There is nothing

which the the being has control over,
which is forms a solid everlasting core,
which is continuous and persists through existence,
worth identifying as a self,

Awareness is also impersonal. It arises due to:

sense-organ,
sense- object and
sense-consciousness

Madhu,piṇḍika Sutta
You have no control over awareness. Say you hear a unpleasant sound. You cannot command: "Stop hearing!". If you hear something pleasant you cannot command: "Do not stop!". Also when say watching something interesting. Memories and thoughts may arise which takes you attention from what you are watching. You cannot command: "Stay with watching only!". This lack of control makes this partly unsatisfactory.
Even the observer is:

impermanent
unsatisfactory
not / non self

Also see: Sutta references which Discuss Self and Not Self under Different Contexts

A "being" ("satta") is a view ("ditthi") made by craving & attachment. "Beings" (sattānaṃ & sattanikāye) are products (abhinibbatti) of "birth" ("jati"). See SN 23.3 http://www.accesstoinsight.org/tipitaka/sn/sn23/sn23.002.than.html and SN 5.10 http://www.accesstoinsight.org/tipitaka/sn/sn05/sn05.010.bodh.html. Regards

With regard to unpleasant sounds, I find that I no longer feel assaulted by them (usually) because it no longer seems to be happening to me. There is sound. If I were to think: "where is the sound happening?" I would not say that it is happening there, at the point my ears say it originates from. Also, I would not say it is happening here, where I would point to me, or inside my mind, or awareness. It is no longer happening here or there, because there is no longer someone it is happening to. (Sometimes not.)

Make sures there is no I or Me conceiving also.

-1 I don't like this use of the skandhas. I know there are plenty of texts which have this understanding, but I don't think it's right. Rather than seeing them as building blocks of reality, it makes more sense to me to see them as a rhetorical aid for investigating the existence (or non-existance) of an individual self.

@GavinSerra this sounds interesting, I wish I better understood you. On the other hand, people cognize in different ways, and the same concept approached differently and spoken of differently can still be just as true, and just as useful. Not sure if the distinction you are making is truly significant, or just point of view difference? How could I find out?

Each skandha covers the whole of reality, and they're each a different perspective from which to view reality. Now... if the Buddha says 'there is no separate, permanent self', our experience of reality is so complex it's hard to know where to begin to look to see if this may be true. So the skandhas are a means of teasing out different perspectives, and from each one, and of each phenomenon therein we can ask 'is this a separate, permanent self?'

This is roughly Red Pine's take from his translation of the Lankavatara Sutra (if I remember correctly), and according to wikipedia, Thannisaro (access to insight) also disagrees with the idea that they're building blocks.

Please correct me if I'm mistaken but in my understanding this is not in alignment with Buddhist teachings

Yeah, this is not in alignment with Buddhist teachings.

We can discover that there is an awareness of thought, emotion etc but are we this awareness?

Most of us are lead to believe that awareness is a continuous thing. According to Buddhism, there are two mistakes in that belief. The first is believing it's continuous. The second is believing it's a thing.
In general, an awareness is an awareness of something. In Buddhism, this is called consciousness, which is six-fold (one for each sense organ, including the mind as a sense organ). These consciousnesses are bindings between sense and object.
So, some people might believe there's an underlying continuous awareness that recognizes a thought. But in Buddhism, we are taught that the moment of recognition is called a contact (between mind organ and thought, "glued" by the mind-consciousness), and before that, there was a very different awareness that was part of another contact with another object through another sense.
The consciousnesses that arise during these events are also called established consciousnesses. It is through contact that there is touching of samsara. When consciousness is not established (i.e. it does not arise), say, when there's no opportunity or interest in "touching anything" (outside, inside, anywhere), then...

“But, bhikkhus, when one does not intend, and one does not plan, and one does not have a tendency towards anything, no basis exists for the maintenance of consciousness. When there is no basis, there is no support for the establishing of consciousness. When consciousness is unestablished and does not come to growth, there is no descent of name-and-form.
-- SN 12.39
“When that consciousness is unestablished, not coming to growth, nongenerative, sn.iii.54 it is liberated. By being liberated, it is steady; by being steady, it is content; by being content, he is not agitated. Being unagitated, he personally attains Nibbāna. He understands: ‘Destroyed is birth, the holy life has been lived, what had to be done has been done, there is no more for this state of being.’”
-- SN 22.53
“If, bhikkhus, one does not intend, and one does not plan, but one still has a tendency towards something, this becomes a basis for the maintenance of consciousness. When there is a basis, there is a support for the establishing of consciousness…. Such is the origin of this whole mass of suffering.
-- SN 12.40

Bhikkhu Sujato also discusses this topic in his blog.

This post is very confusing, particularly when it wrongly states: "When consciousness does not find a footing, when there's no opportunity or interest in "touching anything" (outside, or inside)...." . There is no such thing as consciousness without a sense object. Consciousness without footing refers to the absence of craving rather than to the absence of a sense object (such as Nibbana as a sense object). Please read the whole of SN 22.53 again and also MN 38. When mind objects end in the cessation of perception & feeling (nirodha sampatti), the mind becomes unconscious. Regards.

Perhaps my words are not clear to you, I'm sorry. I did not mean what you said I meant.

Consciousness does not find a footing, that means Nibbana?

@Uuu Only if avijjā/sankhara came to cessation, I suppose. What it seems to me is that cessation of consciousness is a certain focus area. For example, in the perspective of nidanas, through one side, one practices for the end of craving (where the nidanas on the "top" are put in check) and through the other side, simultaneously (and because of it), ignorance starts to give to knowledge, undermining sankhara (putting nidanas in check from the "bottom") -- in this mode, it's like both sides seem to culminate on consciousness. E.g. see also  SN 22.54.

I tried to remove what could be perceived as ambiguous, hopefully it's clearer now

Things that arise due to reasons cease once the reasons cease.
Who or what is observing is panchaupadhänakkhandha
Panchaupadhänakkhandha arise due to a reason and cease once the reason ceases.
The reason for panchaupadhänakkhandha to exist is the liking toward them (chanda). Once the liking toward them ceases to exist, so will panchaupadhänakkhandha cease to exist. This is nibbana.
The method of removing this liking is to understand that panchaupadhänakkhandha in terms of the Four Noble Truths, thereby practicing the Noble Eightfold Path.

Nothing is the observer but there is observing. One must practice just seeing what arises and falls naturally without words and concepts that we use to make a different reality. Conceptual reality is human made as opposed to Ultimately reality that just is what it is, moment by moment, in our experiential awareness.
If you program computers perhaps this will help:
Conceptual reality is to Ultimate reality like
Ruby language is to machine language.
We cannot find a self when we see things as they are. As a rule of thumb, everything we experience is empty of self. Everything. Even the apparent observer or watcher.
Not self simply shows us that we are empty of self as the trees and ponds and lakes obviously are empty of self too. To see anatta is to see yourself as just a bunch of impersonal processes.-Metta

Hard to 'practice'. It is like riding a bicycle: either you are doing it, or you are not. Once you can do it, you are not likely to fall over ever again. No one can 'teach' it to you, and no amount of explanation will describe how to do it. A bit pointless, really. Why do people undertake this?

Sounds good. Teachers are more like guides and why do people undertake what exactly?

Undertake to stop being people. (There is a joke in there somewhere...)

Lol!! ....I think we stop being people because we are to busy being something or someone else.

I think this question 'who is observing' is a blind alley. If in one moment you have a sense that there is observation, or you reflect 'I am observing' or 'I was observing', so what? And if in the next moment there's no such sense or reflection, what then?
These 'who am I' or 'what is observing' questions are common in some types of Zen, but they're not orthodox Soto Zen. Dogen criticised them, and Menzan Zuiho Osho in his Jijuyu-Zanmai says:

Searching for the subject of seeing and hearing is also useless. The
  harder you look for the subject, the more you will become tired of
  wastefully struggling, since what is seeking and what is being sought
  cannot be separated.

Full text here: https://terebess.hu/zen/menzan.html
I'm not a Zen teacher so I'm reluctant to make categorical statements about Buddhism, but I'd say with a reasonable degree of confidence that you're correct that 'we are awareness of thought' is not what Buddhism teaches.
As to meditation, I don't think it helps us to recognise our true nature per se, but it's probably harder to recognise with a head full of thoughts, and Zen meditation generally involves letting go of idle intellection (it's hard to say what is or isn't a misunderstanding of 'mindfulness' these days because the word has become mainstream and none of us can be sure now what it's being used to mean, so it's probably best avoided if you want to get technical).

In Ch'an, the mind (Citta) is always described in a metaphor of a mirror. When you asked Who or what is observing, by observing you've negated the whole to parts: the observer and the observed. With these split, added with negations on negations, the world comes to existence - Samsara, so to speak. Without the observed, the observer cannot come into existence. Now this observer is not the Self, because it depends on the observed to exist. Like we can't see our own face. We can only see ourselves by looking into the mirror, the reflection. It is in this context that the Buddha said, Anatta/not-Self. Because what we termed ourselves are the reflections on the mirror, we know that reflection is "not me". With a dusted mirror, broken mirror, the reflection is bad, therefore we can't even see a proper face of us. Here comes in the meditation, quieting the mind (usually endless chattering, commentary, worry, wish that occupied the mind), you are much clearer in seeing your own face (I think here some incomplete understanding by inserting the term true-Self [your "true authentic self"] comes in).  Like a bucket with murky water, when it's stilled, the water is clear, that is in this condition that insight can come to the mind.
With above stated, I would say, putting Anatta/not-Self everywhere like some conventional Theravadist in English community did is incomplete/ incorrect. I think you are wise in your learning by saying ...Wouldn't Buddha say that even awareness is not self? If we are not thought, not awareness, who or what is the observer?... However, your this question Who or what is observing is coming from an intellectual perspective, the question conditioned the answer, like by saying observing there is observer and observed. They are not an absolute existence but depended on each other. However, to make use of this to track on The Path, it is to be aware moments of moments, i.e., clearing more the observed(s) (chattering, commentary, worry, wish) thus removed the observer(s) becomes more and more single-minded, you will be able to see your true face.
Sometimes in the English Buddhism communities some schools used the term true-Self. In Chinese is 真我. (There are many words 我, 吾, 自己... used in different context, but there are I and Self only in English). I'm afraid since Buddhism was originated in ancient India and reaching prominence in ancient China the English term is rather scarce to convey the meaning in any particular term. Therefore I would avoid using terms such as these.
Addition: Now what is (真)我, or, badly termed Self/true-Self? Like a knife cannot cut itself, an eye cannot see itself, so is this "I" can't see my own face without the mirror, it is here the path of meditation (if anyone is able to reach this stage, at least feeling the body-Self doesn't exist in meditation, which is in fact not yet quiet at it), the journey will be continued without the path.

The mind is often described as a mirror in Ch'an, and this is very orthodox, but I don't get it. It seems to imply a separation between things, and Hui Neng famously denied it. Maybe there's a meaning I'm not gettting...

@GavinSerra Master Neng said, 明鏡亦非臺, flipping his Dharma brother Master Shenxiu's 心如明鏡臺, which he didn't flip 心 (Citta?), but 臺...

If he flipped the totality of this statement, it should be worded as 明鏡亦非心. Hope you could see the graphical difference if you don't read Chinese :) I think it's really quite a complex Dharma contemplation. But I would also say stating "true-Self" barely is quite risky easy resulted misinterpretation. I read somewhere you mentioned Red Pine, I read by chance small bit of his translation I would say he was - hmmm... not really get it, even misunderstood... it will need more space to explain then this little comment box though ;)

I have the Nishijima and Cross Shobogenzo, so I'm used to long tracts of shinji (?) ... :) I've read others criticising Red Pine, so I'd be interested to get your take. His view of the skandhas was already my personal view, so my ego was flattered to find him corroborate :D I will ponder the above shapes a little more (I'm used to this from Dogen)

@GavinSerra hope you're not too wasted with my prolixity :) many seemed contradicted statements can easily be found in Sutras, different masters... bare in mind that what the Path led is leading to what beyond the intellect, consciousness, name-form, concepts, words... to break free from our reality confinement resulted from 無明 (Ignorance?). But what we can do as trapped in the confinement is trying to pull it down to be reached inside this confinement, since we literally has nowhere to go, like Don Quixote pulling himself out from the swamp by pulling at his own hair.

Like the 7 blinds describing one elephant, words are different, but they do describe the elephant. Without the elephant, no description. So is the notion of Anatta. But Theravadist can't go further, truncated there. ...All the not-Self(s) is because of the true-Self, by realizing not-Self the true-Self can be touched unstained. It's not that not-Self vs true-Self only one can be right. The reflection in the mirror is not me, but the mirror can't have a reflection on its own, right? The Buddha chose the right circumstance right audience to teach the right Dharma.

@GavinSerra In response to your "Red Pine" I didn't read and honestly it's not in my plan of study ;0 since I would rather read directly Huineng, Bodhidharma or the Blue Cliff Scroll it's original words. Provided time, I will do a bit of it to have discussion with you ;) maybe...