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?
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).
The section of the Westminster Confession cited above expresses how God’s immutability defines His other attributes by noting that God’s will is unchanging. The same is true of God’s other attributes. Because God is His attributes, His perfection is immutable. His power is immutable. His knowledge is immutable. His goodness is immutable. His glory is immutable. His love is immutable. His truth is immutable. For God to change in His essence and attributes would be for God to cease to be God.
We have to take care when discussing divine immutability because the word “immutability” is a negation. When we say that God is immutable, we are saying that He is not mutable. His essence and attributes do not change. When we say that God is immutable, we are denying of the Creator something that is true only of creatures. Only created beings are mutable. Only created beings are changeable. In other words, when we predicate immutability of God, we are not saying what the divine nature is. We are saying what it is not. We are saying that the divine being is not the same kind of being that creaturely being is.
At the same time, however, we have to make sure that we avoid reading creaturely kinds of immutability into the concept of divine immutability. As Michael Dodds has helpfully observed, some created things like granite, for example, have a limited kind of immutability (The Unchanging God of Love, p. 15). It is not absolute because over time, wind and rain and other forces will change even the hardest piece of stone, but a piece of granite has a relative kind of immutability. Relative to living creatures, it doesn’t change. It is a static, immobile thing. When we say that God is immutable, we are not predicating this kind of creaturely “immutability” to Him. We are not affirming that God is a static, immobile, inert piece of granite. It is true that God is unchangeable, but it is also true that God is love. He is unchangeable love. God is immutable, but He is also “most loving, gracious, merciful, long-suffering, abundant in goodness and truth, forgiving iniquity, transgression, and sin.”
We also have to remember that God is triune. This means that we affirm that God the Father eternally begets the Son, and the Holy Spirit eternally proceeds from the Father and the Son. This eternal begetting and eternal spiration clearly reveal that God is not immutable in the way that a piece of dead granite is relatively immutable. The Creator differs from His creation. God’s eternal generation and eternal spiration are an immutable eternal generation and an immutable eternal spiration, just as God’s eternal willing, eternal knowing, and eternal loving are an immutable willing, immutable knowing, and immutable loving.