What does Galatians 5:2 mean?

The Christians in Galatia were listening to false teachers. These Judaizers were telling them that they must add the works of the law to faith in Jesus in order to be truly right with God (Galatians 2:4). Paul has rejected that teaching. Christ has set us free, Paul insists, by buying our way out of slavery to sin. That deal is done. We are justified before God (Galatians 3:25–29). To begin to follow the law of Moses in order to be justified by God is to miss the point of Christianity entirely. Paul has said repeatedly that it amounts to asking God to judge us by our works and not by Jesus' sinless life and death in our place. It makes us a slave to our inescapable sin.

Now Paul reveals that it's even worse than that. To seek God's approval by following the law of Moses makes Christ's death for our sins worthless. More specifically, Paul says that to "accept circumcision" makes Christ of no help to us. This is a dire remark, and one that needs to be carefully understood.

Paul is not saying nobody should ever be circumcised, or that circumcised people cannot be Christians. This comment is specifically given in the context of a group of false teachers, the Judaizers, who pressured new non-Jewish Christians to be circumcised in order to be welcomed into God's family. These Galatian men likely did not know what to do. After all, every Hebrew in the Old Testament got circumcised. Even Jesus was circumcised under the law!

Paul's point is that either salvation is through faith in Christ alone, or it is through circumcision and the law. It cannot be both. Any addition of works, of any kind, is not the same as a gospel of salvation by grace through faith (Romans 11:6). To choose one is to reject the other. To choose circumcision, for the purpose of "making sure" you are saved is to reject faith in Christ as the only sufficient payment for sin.