What does Galatians 5:12 mean?

Paul has been writing to the Galatian Christians, explaining that they need nothing other than faith in Christ in order to be saved (Galatians 3:23–29). False teachers claim one needs to follow rituals and sacraments to be made right with God (Galatians 2:4). Paul has written some harsh words in Galatians, especially to those who bring a lie (Galatians 1:6–9). At times his other letters deal with false teachers using strong terms.

This, however, may be Paul's most severe comment. He declares angrily that he wishes that those false teachers who are misleading the Galatians would go past circumcision and castrate themselves!

Though it may sound like Paul is just lashing out at his theological enemies, he is not out of control, or speaking without thinking. Not all anger is sinful (Ephesians 4:26). Jesus expressed anger in a righteous way, and for righteous reasons (John 2:13–22; Mark 3:1–5). So, Paul is suggesting something much deeper than a callous physical act. Those who have been castrated can't produce new converts that are like them. In a spiritual sense, then, those who are "castrated" cannot pass along their lies to a future generation. Their false spiritual perspective would die out.

Perhaps Paul also has in mind the pagan cults of the day whose priests did exactly this, castrating themselves in the worship of their gods. Though circumcision under the law of Moses once carried great meaning in Israel, the arrival of Christ has made it meaningless. Now there was only faith in Christ or nothing at all. Circumcision had no more spiritual value in God's eyes after the arrival of Christ than full castration would have.