John of Damascus: Exposition of the Orthodox Faith 61Concerning the deification of the nature of our Lord's flesh and of His will.

It is worthy of note that the flesh of the Lord is not said to have been deified and made equal to God and God in respect of any change or alteration, or transformation, or confusion of nature: as Gregory the Theologian says, "Whereof the one deified, and the other was deified, and, to speak boldly, made equal to God: and that which anointed became man, and that which was anointed became God." For these words do not mean any change in nature, but rather the oeconomical union (I mean the union in subsistence by virtue of which it was united inseparably with God the Word), and the permeation of the natures through one another, just as we saw that burning permeated the steel. For, just as we confess that God became man without change or alteration, so we consider that the flesh became God without change. For because the Word became flesh, He did not overstep the limits of His own divinity nor abandon the divine glories that belong to Him: nor, on the other hand, was the flesh, when deified, changed in its own nature or in its natural properties. For even after the union, both the natures abode unconfused and their properties unimpaired. But the flesh of the Lord received the riches of the divine energies through the purest union with the Word, that is to say, the union in subsistence, without entailing the loss of any of its natural attributes. For it is not in virtue of any energy of its own but through the Word united to it, that it manifests divine energy: for the flaming steel burns, not because it has been endowed in a physical way with burning energy, but because it has obtained this energy by its union with fire.

Wherefore the same flesh was mortal by reason of its own nature and life-giving through its union with the Word in subsistence. And we hold that it is just the same with the deification of the will; for its natural activity was not changed but united with His divine and omnipotent will, and became the will of God, made man. And so it was that, though He wished, He could not of Himself escape, because it pleased God the Word that the weakness of the human will, which was in truth in Him, should be made manifest. But He was able to cause at His will the cleansing of the leper, because of the union with the divine will.

Observe further, that the deification of the nature and the will points most expressly and most directly both to two natures and two wills. For just as the burning does not change into fire the nature of the thing that is burnt, but makes distinct both what is burnt, and what burned it, and is indicative not of one but of two natures, so also the deification does not bring about one compound nature but two, and their union in subsistence. Gregory the Theologian, indeed, says, "Whereof the one deified, the other was deified," and by the words "whereof," "the one," "the other," he assuredly indicates two natures.