How can the Incarnation be reconciled with God's immutability?
The question behind the question is whether "God became man" means God turned into something He was not before. Scripture says both that the Word was God and that the Word became flesh, and commentators handle the tension by asking carefully what exactly changed.
What Changed and What Did Not
Writers consistently locate the change in Christ's position and condition rather than in what He is. One commentator draws the line precisely, noting that the account in John moves straight from the fact of the incarnation to a statement about His glory:
J. T. MawsonThe testimony surely is that in becoming Man He did not surrender what He was before. His circumstances were changed and His condition. He who was in the form of God was now in the form of a servant, He who was the Creator had become a man, in the full sense of that word as God Himself would define it, but He was still the Word, and He is confessed by the disciples as the Son. His relationship with the Father remained as it ever was in those timeless ages before the worlds were made.
The same distinction is drawn from the grammar of John 1 itself — one thing He always was, another thing He became:
F. B. HoleThere is what He was, and what He became; and "The Word" is what He ever was, and "flesh" what He became. The statements are quite definite. Can they be avoided?
Addition, Not Exchange
If deity had been converted into humanity, immutability would indeed be broken. Commentators reject that idea outright. One publication quotes William Kelly on the point:
An Outline of Sound WordsThis becomes all the more remarkable because He deigned for the deepest purposes to become true man. This, however, did not intrude on His deity, for incarnation means not Godhead swamped by humanity, but this taken into everlasting union with itself, each nature abiding in its own perfectness, not changed into something else, but constituting together the one person of Christ.
Others put it as a gain to His manhood rather than a loss to His Godhead:
E. C. HadleyHe took up perfect manhood into union with His Person. His incarnation did not in the least detract from His eternal deity nor from His eternal relationship in the Godhead, but only gave to His humanity His infinite perfection.
The Emptying That Kept Deity Intact
Philippians speaks of Christ emptying Himself, and that word is where many suspect a change in His nature. The explanation offered is that what He set aside was the display and use of divine prerogatives, not the divine nature:
William KellyDeity is manifested by the exercise of its attributes and prerogatives. In His incarnation, these were suppressed by Christ, but were not abandoned, which could not be... When Christ Jesus emptied Himself for obedience, He was still God, for it could not be otherwise. But, if we may so speak, He was pleased that in His incarnation His deity should remain quiescent, and His bond-service appear.
Note the phrase "could not be." The reasoning runs the other way from the objection: because God cannot change, laying deity aside was never an option. As another writer states it, since the Word was God and the Creator of everything, "He could never cease to be God."
Manhood Taken Up Permanently
The incarnation was not a temporary costume worn for thirty-three years and then discarded. That matters, because a God who put manhood on and off would be a changeable God:
J. T. MawsonHis humanity was not in form merely, something put on, as one would put on a garment for a certain purpose and then cast it off again when that purpose was accomplished, but it was a reality. He became an actual man, and this He will never cease to be.
This is where Hebrews 13:8 lands: the One who does not change is now, permanently, both God and man.
Samuel RidoutHis yesterday on earth is the same as His today on the throne; and forever His future will present to us the One who never changes; the One who is, who was, and is to come — God and Man in two distinct natures, but one person forever.
Where Reconciling Stops
Commentators are candid that the two truths are held, not solved. The advice given is to refuse the pressure to force them into a system:
Samuel RidoutOur safety lies in holding fast to all that Scripture reveals, not seeking unduly to harmonize it, but recognizing that whatever God states must be true, and, were we able for it, capable of perfect understanding. Indeed there is no difficulty for humble faith in apprehending all sides of the truth as to the Son of God. Unbelief alone stumbles here.
And there is a reason the mind cannot close the gap, one that follows from being a creature at all:
A. J. PollockThe person of Jesus is an inscrutable mystery, which no human intelligence can understand. The intellectual powers and wit of men are of no use here. It must be so. If I, a mere creature, could understand the Creator, I should no longer be a creature.
Summary
- Became, not changed. John says what He was (the Word) and what He became (flesh); His condition and circumstances changed, what He is did not.
- Taken up, not traded. Manhood was drawn into union with His Person, each nature keeping its own perfectness — an addition to His humanity's glory, not a subtraction from His deity.
- Veiled, not surrendered. In emptying Himself He suppressed the exercise of divine prerogatives; abandoning the divine nature "could not be."
- Kept, not discarded. The manhood is real and permanent — He will never cease to be Man, so the unchanging One is now God and Man in one person forever.
- Held, not solved. Commentators advise holding every side Scripture states without forcing a harmony; a creature who could fully explain the Creator would no longer be a creature.