In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God. . . . And the Word became flesh and dwelt among us, and we have seen his glory, glory as of the only Son from the Father, full of grace and truth. (John 1:1–2, 14, emphasis added)
The words that open the gospel of John are among the most astounding and wondrous words in all Holy Scripture. A Christian could spend his entire life meditating on the meaning of these sentences, and at the end of his life he will at most have only scratched the surface. The Apostle John speaks here of one of the most profound mysteries of the Christian faith, the incarnation of the eternal Son of God, the One who was in the beginning with God, the One who was with God, the One who is God.
But what does it mean to say that the Word, the Son of God, became flesh? Does it mean that God transformed into a man? Does it mean that God’s nature and man’s nature were blended somehow to create a new hybrid nature? Does it mean that God changed?
THE IMMUTABILITY OF GOD
The question is important because Scripture teaches and orthodox Christians have always taught that God’s nature is, by definition, immutable. Article 1 of the Belgic Confession, for example, states:
We all believe with the heart, and confess with the mouth, that there is one only simple and spiritual Being, which we call God; and that he is eternal, incomprehensible invisible, immutable, infinite, almighty, perfectly wise, just, good, and the overflowing fountain of all good. (Emphasis added)
The Westminster Confession of Faith, likewise, states:
There is but one only, living, and true God: who is infinite in being and perfection, a most pure spirit, invisible, without body, parts, or passions, immutable, immense, eternal, incomprehensible, almighty, most wise, most holy, most free, most absolute, working all things according to the counsel of His own immutable and most righteous will, for His own glory; most loving, gracious, merciful, long-suffering, abundant in goodness and truth, forgiving iniquity, transgression, and sin; the rewarder of them that diligently seek Him; and withal, most just and terrible in His judgments, hating all sin, and who will by no means clear the guilt. (WCF 2.1, emphasis added)
Orthodox Christians have always taught that God is immutable because that is what God has revealed about His nature in Scripture. He proclaims through the prophet Malachi, for example, “I the LORD do not change” (Mal. 3:6). In the New Testament, we see the same. James, for example, writes: “Every good gift and every perfect gift is from above, coming down from the Father of lights, with whom there is no variation or shadow due to change” (James 1:17).