"Jesus Christ is the same yesterday and today and forever."
Every year at this time as we celebrate the birth of baby Jesus to the virgin Mary, I don't suppose it occurs to too many merrymakers that what they're really celebrating is the Incarnation. All of the other miracles are in service of that central miracle: God became man. And in becoming, through Spiritual conception, the man Jesus of Nazareth, the Word of God did not cease to be God. Baby Jesus, from the moment of conception to the straw habitation of the manger, was fully God and fully man. That's what Christmas is all about, Charlie Brown.
When we put our minds long to the idea of Jesus being one hundred percent God and simultaneously one hundred percent man, they naturally feel overwhelmed. The orthodox doctrine of the Incarnation is compelling, beautiful, biblically sensible, and salvifically necessary, but it is nevertheless utterly inscrutable. And that's okay. In the end, the Incarnation is not for analysis but for worship.
But when we read Colossians 2:9—- "For in him the whole fullness of deity dwells bodily"—- the inscrutability of the Incarnation widens. The baby Jesus who was wrapped in swaddling clothes, lying in a manger, was also omnipresent Lord of the universe. Omnipresence is one of God's impassable attributes; God cannot not be omnipresent. So for Jesus Christ to be God incarnate must not mean he was no longer God omnipresent.
Louis Berkhof concurs:
The doctrine of creation and the doctrine of the incarnation always constituted a problem in connection with the immutability of God… However this problem may be solved, it should be maintained that the divine nature did not undergo any essential change in the incarnation.
Wait a second, you might say. Didn't Jesus disregard his deity as something to be grasped? Yes, but what Paul is getting at in Philippians 2:5-8 is not that Jesus did not "hold" or "maintain" the fullness of his divinity but that he did not exploit it or leverage it against his experiencing the fullness of humanity. He didn't pull the parachute, in other words.
Instead, what we see in the wonder of the God-Man is a miraculous extension, not reduction. Jesus "made himself nothing" (Phil. 2:7), yes, but this was not a voiding of his essential deity. It is instead an appraisal of the bewilderment of the Incarnation. The Incarnation posits a self-willed emptying consisting of Jesus' refusal to employ all divine abilities at his disposal, not an emptying that would consist in a subtraction from the Godhead. The alternatives to simultaneous incarnation and omnipresence are a lesser incarnation on one side or a lesser Godhead on the other.
The words of John Calvin:
For even if the Word in his immeasurable essence united with the nature of man into one person, we do not imagine that he was confined therein. Here is something marvelous: the Son of God descended from heaven in such a way that, without leaving heaven, he willed to be borne in the virgin's womb, to go about the earth, and to hang upon the cross; yet he continuously filled the world even as he had done from the beginning!**
In Calvin's estimation, God's incarnation in Christ was not an exit from heaven so much as a descent, an extension. In his commentary on John's Gospel, he writes, "So Christ, who 'is in heaven,' has clothed himself in our flesh, so that by stretching out his brotherly hand to us he may raise us to heaven with himself."***
Let us take this cue from Calvin: Here is something marvelous!
This Christmas, let's marvel that the Incarnation presents to us the fullness of God in the fullness of man, because it proclaims to us the great big gospel of the fullness of God for the fullness of man.
* Louis Berkhof, Systematic Theology (Grand Rapids, Michigan: Eerdmans, 1996), 323-324.
** John Calvin, Institutes of the Christian Religion, edited by John T. McNeill, Vol. 1, 2.XIII.iv (Philadelphia: Westminster, 1960), 481.
*** John Calvin, Crossway Classic Commentaries, Packer (Wheaton: Crossway, 1994) 74‐75. John 17:21