What Scriptures did Arius use to support teaching that Jesus was created? Arius probably quoted the following:

Revelation 3:14: These things saith the Amen, the faithful and true witness, the beginning of the creation of God.
Psalm 8:5–6: thou madest Him
Proverbs 8:22–25: the LORD possessed [H7069 strongs, get, acquire, create] me in the beginning of his way, before his works of old... when there were no depths I was brought forth.

What other scriptures did Arius use to support his teaching that Jesus was created?
In the early fourth century, many Christians were divided over how best to understand the relationship between God and Jesus. Emperor Constantine called for an ecumenical council of bishops to settle the matter: the Council of Nicea, in 325 AD. The result was a condemnation of 'the Arian heresy'.

Letter to Emperor Constantine
A few years later, in 327 AD, Arius and his ally Euzoïus addressed a letter to Emperor Constantine to explain what their beliefs were. (Presumably, they didn't trust their trinitarian opponents to accurately represent them.) Arius wrote:

We believe in one God the Father Almighty, and in the Lord Jesus Christ his son, who was begotten of him before all ages, God the Word through whom all things were made, both things in heaven and on earth; who descended, and became human, and suffered, and rose again, ascended into heaven, and will again come to judge the living and the dead. We believe also in the holy spirit, and in the resurrection of the flesh, and in the life of the coming age, and in the kingdom of the heavens, and in one catholic church of God, extending from one end of the earth to the other.
This faith we have received from the holy gospels, in which the Lord says to his disciples, ‘Go and teach all nations, baptizing them in the name of the Father, and of the son, and of the holy spirit.’ If we do not so believe and do not truly receive the Father, the son, and the holy spirit, as the whole catholic church and the holy scriptures teach (in which we believe in every respect), may God judge us both now, and in the coming judgment.

In the second paragraph cited above, Arius included Matthew 28.19, a verse often used to argue for the trinity. By citing this passage, Arius was showing that he was not ignorant of its existence, and thus implicitly that he did not believe it taught a trinitarian theology.
The first paragraph above, Arius presents the beliefs of his group in the form of a creed. (The shape of this creed was possibly in direct response to the Nicene Creed that had been drafted at the council.) Notably, Arius' creed begins with an apparent allusion to 1 Corinthians 8.6 ('We believe in God the Father Almighty, and in the Lord Jesus Christ his son'). Because Paul identifies each 'God the Father' and 'the Lord Jesus Christ', Arius seems to have taken this as a hard distinction between the two. This is a starting point, but very little else is readily discernible from this letter.

Letter to Alexander
A much more accessible letter to work with would be Arius' letter to Alexander circa 320 AD. Alexander was the bishop of Alexandria, and one of Arius' opponents. In this letter, Arius wrote his group's beliefs:

We acknowledge one God, alone unbegotten, alone everlasting, alone without beginning, alone true, alone having immortality, alone wise, alone good, alone sovereign, judge, governor, and provider of all, unalterable and unchangeable, just and good, God of the Law and the Prophets and the New Covenant. Who begat an only-begotten son before time and the ages, through whom he made both the ages and all that was made; who begot him not in appearance, but in reality; and that he made him subsist at his own will, unalterable and unchangeable, the perfect creature of God, but not as one of the creatures; offspring, but not as one of the other things begotten.

Now we have something to work with. Arius provides a dense cluster of allusions to Old and New Testament scripture, giving us a much stronger sense of his approach to the Bible as a whole:

&quot;We acknowledge one God&quot; — Presumably Deuteronomy 6.4 would be the ultimate origin of his point, but the phrase 'one God' is scattered throughout both Old and New Testaments.
&quot;Alone unbegotten&quot; — Psalm 2.7 would be the ultimate origin of this, as this psalm was popularly associated with Jesus (e.g. Acts 13.33; Hebrews 1.5). Arius took this to mean that, if Jesus was 'begotten', he must have had a beginning. This would go on to become one of the chief arguments used by Arius and those in agreement with him.
&quot;Alone everlasting&quot; — Possibly Isaiah 40.28 (Isaiah 40-55 has numerous examples of monotheistic proclamations), or perhaps Romans 16.26.
&quot;Alone true&quot; — John 17.3, where in prayer Jesus identifies the Father as 'the only true God'. While the Hebrew term 'elohim and the Greek term theos may be applied in various ways to human, angelic, or even demonic entities, Arius took this verse to mean that the Father alone could truly be identified with the term 'God', and thus not Jesus.
&quot;Alone having immortality&quot; — This is an explicit reference to 1 Timothy 6.15-16, where the author of the epistle wrote that God 'alone has immortality' (cf. 1 Timothy 1.17). Since God (whom Arius had already identified one-to-one with 'the Father') is alone immortal, Arius reasoned that Jesus was not immortal in the same sense, and thus not 'God'.
&quot;Alone wise&quot; — Romans 16.27, where Paul concludes his letter with a benediction 'to the only wise God forevermore through Jesus Christ!'
&quot;Alone good&quot; — Mark 10.18. Arius read this to mean that Jesus denied being God.
&quot;Alone sovereign, judge, and governor&quot; — 1 Timothy 6.15, where the author of the epistle says God is 'the only sovereign, the king of kings, and lord of lords' (cf. 1 Timothy 1.17).

Later in the same letter, Arius wrote:

Therefore he thus has his being from God; and glories, and life, and all things have been given over to him; in this way God is his beginning. For he is over him, as his God and being before him. But if the expressions 'from him' and 'from the womb' and 'I came from the Father, and I have come', are understood by some to mean that he is part of him, one in essence or as an emanation, then the Father is, according to them, compounded and divisible and alterable and material, and as far as their belief goes, the incorporeal God endures a body.

Here Arius explicitly cites three passages to distinguish Jesus as having a beginning and origin, in contrast to 'the eternal God'. Presumably, the passages Arius is quoting from were:

&quot;from him&quot; — John 6.46.
&quot;from the womb&quot; — Psalm 110.3.
&quot;I came from the Father, and I have come&quot; — John 16.28.


Thalia
Arius also wrote a poem titled Thalia, though it is uncertain when the poem was written, or even if what we have is an authentic copy of the text. (All we have is provided by his opponents.) The existing text does allude to Proverbs 8.22-25, and possibly also combines it with Revelation 3.14:

He who is without beginning made the Son a beginning of created things

and

Wisdom came to be Wisdom by the will of the Wise God
. . .
The one who is superior is able to beget one equal to the Son


Summary
We could continue, but I think this is enough to demonstrate the key passages Arius relied on, as well as his general hermeneutic to the scriptures. Whenever Arius saw a biblical author speaking of 'one God', or that God 'alone' had an attribute, he took this as antithetical to a trinitarian theology. Whenever Arius saw a biblical author distinguishing between 'God' and 'Jesus', he took this to mean Jesus was not himself God.