Scriptural Basis for the Doctrine of Deification/Theosis

Ps. 82: 5-6
5 They know not, neither will they understand; they walk on in darkness: all the foundations of the earth are out of course.
6 I have said, Ye are gods; and all of you are children of the most High.
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(cf. John 10: 34-36)
34 Jesus answered them, Is it not written in your law, I said, Ye are gods?
35 If he called them gods, unto whom the word of God came, and the scripture cannot be broken;
36 Say ye of him, whom the Father hath sanctified, and sent into the world, Thou blasphemest; because I said, I am the Son of God?

"The quotation from 2 Peter 1:4 was first used by Origen (thrice), then by Athanasius (six times), and subsequently by Cyril (more than forty times). It appears in the Macarian Homilies (ten times), and then Maximus the Confessor (twice). Symeon the New Theologian appeals to it once, Palamas to give a detailed exegesis of the text." (See:"Partakers of the Divine Nature" (2 Peter 1:4) in the Byzantine Tradition;a detailed article of the doctrine of Theosis as taught by the Greek Orthodox Church; From the hommage to Joan Hussey ΚΑΘΗΓΗΤΡΙΑ, Porphyrogenitus Publ., Camberley UK, 1998)