Researched by the Ignaria Editorial Team · Published 2026-04-19
The doctrine of theosis — that salvation involves genuine participation in divine nature — is the dominant soteriological category of the Greek Fathers. Irenaeus grounded it in the incarnation: the Word became what we are so that we might become what the Word is. Athanasius sharpened the formula in On the Incarnation: "He was made man that we might be made God." Gregory of Nyssa developed it as an unending ascent into the limitless depths of divine life, drawing on 2 Peter 1:4's language of becoming "partakers of the divine nature." Western Christianity has largely answered the salvation question with forensic justification; Eastern Christianity answers it with theosis. The patristic sources in Ignaria show this was not a fringe idea but the mainstream soteriology of the first Christian centuries.
What the primary sources show
Athanasius argues that the Logos assumed human nature to reverse Adam's corruption, granting immortality and enabling genuine participation in divine nature. His "God became man that man might become God" is the foundational statement of Eastern soteriology and theosis.
"For it was for this end that the Word of God was made man, and He who was the Son of God became the Son of man, that man, having been taken into the Word, and receiving the adoption, might become the son of God" — Irenaeus frames theosis as the purpose of the incarnation itself.