What does Galatians 3:12 mean?

The Christians in Galatia are being lured away from the truth. Under pressure from a group known as the Judaizers, they are drifting away from believing they have been saved by God's grace through their faith in Christ alone (Galatians 1:6–9). The Judaizers have presented convincing-sounding arguments that God requires their men to be circumcised (Galatians 2:4). They claim all men must follow the law of Moses to truly be right with God, even after believing in Jesus.

Paul has confronted these false ideas head on, showing from the Old Testament Scriptures themselves that to live under the law is to live under a curse (Deuteronomy 27:26) and that even then the righteous live by faith (Habakkuk 2:4). Now, before turning to Christ, Paul adds that the law is not of faith, it is of works. Those who live under the law must "do" those works without fail (Leviticus 18:5).

In other words, faith and law cannot be made to work together to be made right with God. Those who live under the law must do what it says. Period. If not—and nobody can perfectly follow the law—they are cursed. Those who live by faith in God are trusting God, specifically Jesus' life and death in their place, to be made right with the Father. The Judaizers were telling people they needed both Christ and the law. Paul insists that the two cannot be merged; they are completely separate.