Thereafter he shows that there are not two Christs or two Lords, but one Christ and one Lord, and that the Divine nature, after mingling with the Human, preserved the properties of each nature without confusion, and declares that the operations are, by reason of the union, predicated of the two natures in common, in the sense that the Lord took upon Himself the sufferings of the servant, and the humanity is glorified with Him in the honourthat is the Lord's, and that by the power of the Divine Nature that is made anew, conformably with that Divine Nature Itself
But if we are to discuss the other points in the same way, let us consider what it is that dies, and what it is that destroys death; what it is that is renewed, and what it is that empties itself. The Godhead “empties” Itself that It may come within the capacity of the Human Nature, and the Human Nature is renewed by becoming Divine through its commixture with the Divine. For as air is not retained in water when it is dragged down by some weighty body and left in the depth of the water, but rises quickly to its kindred element, while the water is often raised up together with the air in its upward rush, being moulded by the circle of air into a convex shape with a slight and membrane-like surface, so too, when the true Life that underlay the flesh sped up, after the Passion, to Itself, the flesh also was raised up with It, being forced upwards from corruption to incorruptibility by the Divine immortality.
And as fire that lies in wood hidden below the surface is often unobserved by the senses of those who see, or even touch it, but is manifest when it blazes up, so too, at His death (which He brought about at His will, Who separated His soul from His Body, Who said to His own Father “Into Your hands I commend My Spirit,” Who, as He says, “had power to lay it down and had power to take it again”), He Who, because He is the Lord of glory, despised that which is shame among men, having concealed, as it were, the flame of His life in His bodily Nature, by the dispensation of His death, kindled and inflamed it once more by the power of His own Godhead, fostering into life that which had been brought to death, having infused with the infinity of His Divine power that humble first-fruits of our nature, made it also to be that which He Himself was— making the servile form to be Lord, and the Man born of Mary to be Christ, and Him Who was crucified through weakness to be Life and power, and making all that is piously conceived to be in God the Word to be also in that which the Word assumed, so that these attributes no longer seem to be in either Nature by way of division, but that the perishable Nature being, by its commixture with the Divine, made anew in conformity with the Nature that overwhelms it, participates in the power of the Godhead, as if one were to say that mixture makes a drop of vinegar mingled in the deep to be sea, by reason that the natural quality of this liquid does not continue in the infinity of that which overwhelms it. This is our doctrine, which does not, as Eunomius charges against it, preach a plurality of Christs, but the union of the Man with the Divinity, and which calls by the name of “making” the transmutation of the Mortal to the Immortal, of the Servant to the Lord, of Sin to Righteousness, of the Curse to the Blessing, of the Man to Christ. What further have our slanderers left to say, to show that we preach “two Christs” in our doctrine, if we refuse to say that He Who was in the beginning from the Father uncreatedly Lord, and Christ, and the Word, and God, was “made,” and declare that the blessed Peter was pointing briefly and incidentally to the mystery of the Incarnation, according to the meaning now explained, that the Nature which was crucified through weakness has Itself also, as we have said, become, by the overwhelming power of Him Who dwells in It, that which the Indweller Himself is in fact and in name, even Christ and Lord?
Source: Against Eunomius (New Advent)