 For Paul, when it comes to the Covenant, Gentiles get in and stay in by the Spirit alone. The Galatians had abandoned this train of thought. Thinking they didn't have enough skin in the game, they opted to be circumcised in accordance with God's command, and who could argue with that? Paul could. He may not have had a problem with his fellow Jews abiding by the law, but he refused to allow his Gentile churches to do the same. Paul argues against the law from the law. Accuses the Galatians of being under a spell and wishes that the knife would slip and castrate the one who's holding it. There's a cold steel edge here that's resulted in 2,000 years of anti-Semitism on the part of the church, making Galatians an incredibly difficult read. May we have eyes to see and ears to hear.