Why Did God Become Man?
Couldn't God just forgive us?
Main teaching: De fide
The big question
If God is all-powerful and all-merciful, why didn’t he simply forgive the human race and leave it at that? Why the Incarnation, the long years in Nazareth, and above all the Cross? Couldn’t God just say “you are forgiven”?
What the Church teaches
The Son of God became man “for us men and for our salvation” (Nicene Creed; DH 150).
How sure is this? De fide. It is an article of the Creed.
The Catechism gives four reasons why the Word became flesh (CCC 457–460):
- To save us by reconciling us with God.
- So that we might know God’s love.
- To be our model of holiness.
- To make us sharers in the divine nature.
How the Incarnation relates to God’s freedom is a matter of theological explanation, not definition. Aquinas’s view, which most theologians follow, is that God was not forced to become man, but that it was the most fitting way to save us (Summa III, q. 1, a. 2).
Where it comes from
Scripture. The angel tells Joseph the child’s name and its meaning: “you shall call his name Jesus, for he will save his people from their sins” (Matthew 1:21). Jesus says he came “not to be served but to serve, and to give his life as a ransom for many” (Mark 10:45). St Paul puts it simply: “Christ Jesus came into the world to save sinners” (1 Timothy 1:15).
The deepest reason is love: “For God so loved the world that he gave his only-begotten Son, that whoever believes in him should not perish but have eternal life” (John 3:16). St John adds: “In this is love, not that we loved God but that he loved us and sent his Son to be the expiation for our sins” (1 John 4:10).
The early Church. The Fathers loved to put the purpose of the Incarnation as an exchange. St Irenaeus (died about 202) wrote that Christ became what we are so that he might bring us to be what he is (Against Heresies 5, preface). St Athanasius (died 373) said it even more boldly: the Son of God became man so that we might become God, meaning sharers in God’s life by grace (On the Incarnation 54; CCC 460).
How theologians explain it
St Anselm’s answer. In Why God Became Man (Cur Deus Homo, 1098), St Anselm of Canterbury gave the most famous answer to this lesson’s question. His argument runs:
- Sin dishonours God and breaks the order of justice. Restoring it requires satisfaction, making amends greater than the offence.
- Only a human being ought to make that satisfaction, since humans sinned.
- But only God can make it, since an offence against the infinite God calls for something of infinite worth, and everything humans have already belongs to God.
- So the satisfaction must be made by one who is both God and man.
Anselm’s point is not that God is touchy about his honour. It is that God takes human beings and justice seriously enough to restore humanity from within, through a man, rather than overlook what was done.
St Thomas’s refinement. Aquinas agreed with much of Anselm, but added an important qualification. God could have forgiven sin simply by his mercy, without any satisfaction, since he is not bound by any law above himself (Summa III, q. 46, a. 2, ad 3). The Incarnation was not necessary in that strict sense. But it was the most fitting way, because it shows both God’s justice and his mercy together, and it does far more than cancel a debt (Summa III, q. 1, a. 2; q. 46, a. 3):
| What the Incarnation does | How |
|---|---|
| Shows how much God loves us | He gave his own Son |
| Gives us an example | Of obedience, humility, patience and love |
| Restores human dignity | Human nature is united to God himself |
| Frees us from sin justly and mercifully | A man makes amends, and God’s mercy provides that man |
| Gives us a share in God’s life | The exchange the Fathers described |
An open question. Would the Son have become man if Adam had never sinned? Aquinas thought Scripture always connects the Incarnation with sin, so probably not (Summa III, q. 1, a. 3). Bl. John Duns Scotus (died 1308) and his followers held that Christ was God’s first intention in creating, and would have come anyway, to crown creation. The Church has never decided between them.
Philosophy bridge
The philosophy course’s Ethics branch treats justice as giving each their due, and the restoration of justice as making good an order that has been broken. Anselm’s argument depends on that idea. Satisfaction is not a fine paid to an angry ruler; it is the repair of a relationship that justice requires.
What the Church does not claim
- Not that God had no choice. God freely chose this way of saving us; he was not forced into it.
- Not that God needed to be paid off. Satisfaction is about restoring justice and friendship, not about God being owed compensation for injured feelings.
- Not that the Incarnation was only “plan B”. Whether the Son would have come without the Fall is an open question; both answers are held by Catholic theologians.
- Not that the Incarnation was only about the Cross. Christ’s whole life, from Bethlehem to the Ascension, is part of how he saves us (CCC 517–518).
Check your understanding
- Give the four reasons the Catechism gives for the Incarnation.
Show answer
To save us by reconciling us with God; so that we might know God’s love; to be our model of holiness; to make us sharers in the divine nature.
- Summarise St Anselm’s argument in Why God Became Man.
Show answer
Sin calls for satisfaction. Only a human ought to make it, because humans sinned; only God can make it, because the offence is against the infinite God. So it must be made by one who is both God and man.
- Could God have forgiven sin without the Incarnation, according to Aquinas?
Show answer
Yes. God could have forgiven by mercy alone. But the Incarnation was the most fitting way, because it shows both justice and mercy, gives us an example, restores our dignity, and gives us a share in God’s life.
- Explain St Athanasius’s saying that God became man “so that we might become God”.
Show answer
It means that by uniting himself to our nature, the Son makes it possible for us to share in God’s own life by grace. We do not become God by nature, but become sharers in the divine nature (2 Peter 1:4).
- On what question did Aquinas and Scotus disagree, and has the Church decided it?
Show answer
Whether the Son would have become man if Adam had not sinned. Aquinas thought probably not; Scotus thought he would have come anyway. The Church has not decided it.