The incarnation

The Word became flesh

The word comes from the Latin for ‘enfleshment’ and goes back to what John says of the Word who was God from the beginning:

The Word became flesh and made His dwelling among us. We have seen His glory, the glory of the one and only Son from the Father, full of grace and truth.

John 1:14

‘Flesh’, sarx (σάρξ), here means not just a body but a whole human being, frail and mortal. Augustine explains that it is said "that the Word was made flesh; meaning that the Word was made man" Augustine. So the church confesses that the Son took a human soul as well as a body: the whole of our nature. Nor does ‘became’ mean that he turned into something else. As Chrysostom puts it, "He did not change His substance into flesh … but remaining what He was, took upon Him the form of a servant" Chrysostom. The Son did not subtract his divinity; he added our humanity.

It happened at the time God chose: "when the time had fully come, God sent His Son, born of a woman, born under the law" (Galatians 4:4). He was conceived by the Holy Spirit and born of the virgin Mary (Luke 1:35), and his name is Immanuel, "God with us" (Matthew 1:23).

Why God became man

Scripture gives several reasons. No one has ever seen God, but the Son "has made Him known" (John 1:18). God as God cannot die, but the Son "shared in their humanity, so that by His death He might destroy him who holds the power of death" (Hebrews 2:14). He "had to be made like His brothers in every way" to become our merciful and faithful high priest (Hebrews 2:17). And he came to bring us into the life of God, making us "partakers of the divine nature" (2 Peter 1:4).

Athanasius put the last point boldly: "He was made man that we might be made God" Athanasius, On the Incarnation. He meant sharing by grace in God's life, not becoming God by nature. In the eleventh century Anselm argued that only one who is both God and man could repay the debt of sin, since man owed it and only God could pay it Anselm, Cur Deus Homo (see the satisfaction theory).

How the church confessed it

Some early teachers could not believe that God would truly take flesh, and said that Christ's body only seemed real. This view, called docetism, spread with Gnosticism. John had already written that "every spirit that confesses that Jesus Christ has come in the flesh is from God" (1 John 4:2), and early in the second century Ignatius of Antioch insisted that Christ truly suffered and truly rose, not in mere appearance Ignatius, Letter to the Smyrnaeans. The Nicene Creed confesses the Son:

Who, for us men and for our salvation, came down from heaven, and was incarnate by the Holy Spirit of the virgin Mary, and was made man

The Nicene Creed

The next question was how God and man are one in him. When Apollinarius taught that Christ had no human mind, Gregory of Nazianzus answered that "that which He has not assumed He has not healed" Gregory of Nazianzus, Letter 101. The Council of Chalcedon (451) confessed two natures in one person, and the title Theotokos for Mary guarded the truth that the child she bore was the Son of God himself. Nor is the incarnation a past episode. The Westminster Shorter Catechism confesses that the Son "became man and so was, and continueth to be, God and man in two distinct natures, and one person, forever" Westminster Shorter Catechism, Q. 21.

Paul pictures the incarnation as the Son emptying himself and taking the form of a servant (Philippians 2:7). The classic reading of the Fathers and the Reformation confessions is that he emptied himself by taking our nature, not by giving up any part of his own. From the nineteenth century some theologians proposed kenotic theories, in which the Son laid aside his divine attributes, or their use, during his earthly life. Both readings confess that he became truly human and never ceased to be God. His path from lowliness to glory is traced under humiliation and exaltation. See also the lesson The incarnation and Why did God become human?