He labours to draw them away from circumcision. He shows them the battle between the Spirit and the flesh, and the fruits of them both.

5 Stand fast therefore in the liberty whereby Christ has made us free, and do not wrap yourselves again in a yoke of bondage. ² Behold, I Paul say to you that if you are circumcised, Christ will profit you nothing at all. ³ I testify again to every man who gets circumcised that he is bound to keep the whole law. ⁴ You are gone quite from Christ, as many of you as would be justified by the law, and are fallen from grace. ⁵ We look for and hope in the Spirit to be justified through faith.