“That we may the better behold the glory of Christ herein, we may briefly consider the especial nature of this condescension, and wherein it doth consist.
But whereas not only the denial, but misapprehensions hereof, have pestered the church of God in all ages, we must, in the first place, reject them, and then declare the truth.
This condescension of the Son of God did not consist in a laying aside, or parting with, or separation from, the divine nature, so as that He should cease to be God by being man.
The foundation of it lay in this, that he was ‘in the form of God, and thought it not robbery to be equal with God,’ (Phil 2:6);—that is, being really and essentially God in His divine nature, He professed Himself therein to be equal with God, or the person of the Father.
He was in the form of God,—that is, He was God, participant of the divine nature, for God hath no form but that of His essence and being; and hence He was equal with God, in authority, dignity, and power.
Because He was in the form of God, He must be equal with God; for there is order in the Divine Persons, but no inequality in the Divine Being.
So the Jews understood Him, that when He said, ‘God was His Father, He made Himself equal with God.’
For in His so saying, He ascribed unto Himself equal power with the Father, as unto all divine operations. ‘My Father,’ saith He, ‘worketh hitherto, and I work,’ (John 5:17-18).
And they by whom his divine nature is denied do cast this condescension of Christ quite out of our religion, as that which hath no reality or substance in it. But we shall speak of them afterward.
Being in this state, it is said that he took on Him the form of a servant, and was found in fashion as a man, (Phil. 2:7). This is His condescension.
It is not said that He ceased to be in the form of God; but continuing so to be, He ‘took upon Him the form of a servant’ in our nature: He became what He was not, but He ceased not to be what He was.
So He testifieth of Himself, (John 3:13), ‘No man hath ascended up to heaven, but be that came down from heaven, the Son of man which is in heaven.’
Although He was then on earth as the Son of man, yet He ceased not to be God thereby;—in His divine nature He was then also in heaven.
He who is God, can no more be not God, than He who is not God can be God; and our difference with the Socinians herein is,—we believe that Christ being God, was made man for our sakes; they say, that being only a man, he was made a god for His own sake.
This, then, is the foundation of the glory of Christ in this condescension, the life and soul of all heavenly truth and mysteries,—namely, that the Son of God becoming in time to be what He was not, the Son of man, ceased not thereby to be what He was, even the eternal Son of God.”
–John Owen, “Meditations and Discourses on the Glory of Christ,” The Works of John Owen, Volume 1: The Glory of Christ (Carlisle, PA: Banner of Truth, 1684/2000), 1: 325–326.