Paul wants to make it clear that those encouraging circumcision were not thoroughgoing observers of the law. 1 They expect law obedience at certain points, but they themselves are disobedient to the same law. 2 Highlighting the hypocrisy of the Judaizers, he once again affirms that you cannot win God’s favour through your own sinful law obedience. His words are similar to those that Jesus spoke to the Pharisees (see Matthew 23:1–39). He would repeat the same idea at a later stage when he writes to the Christians in Rome (Romans 2:17–24). 3
13 For even those who are circumcised do not themselves keep the law, but they desire to have you circumcised that they may boast in your flesh.