Daily Reading for December 4 • John of Damascus, Priest, c. 760
So then, after the assent of the Holy Virgin, the Holy Spirit descended on her . . . purifying her, and granting her power to receive the divinity of the Word, and likewise power to bring forth. And then was she overshadowed by enhypostatic Wisdom and the Power of the most high God, the Son of God Who is of like essence with the Father as of Divine seed, and from her holy and most pure blood He formed flesh animated with the spirit of reason and thought, the first-fruits of our compound nature; not by procreation but by creation through the Holy Spirit; not developing the fashion of the body by gradual additions but by perfecting it at once, He Himself, the very Word of God, standing to the flesh in the relation of subsistence. For the divine Word was not made one with flesh that had an independent preexistence, but taking up His abode in the womb of the holy Virgin. . . . So that He is at once flesh, and at the same time flesh of God and the Word, likewise flesh animated, possessing both reason and thought. Wherefore we speak not of man as having become God, but of God as having become man.
From Exposition of the Orthodox Faith by John of Damascus, quoted in Invitation to Christian Spirituality: An Ecumenical Anthology, edited by John R. Tyson (Oxford University Press, 1999).