John Trapp on Galatians 6:13

Verſe 13. Keep the law] Rom. 2.23. Hierome doubteth not to pronounce that man accurſed, that ſaith it is impoſſible to keep the Law. Sed quid viſum ſit Hieronymo, nihil moramur: nos quid verum ſit inquirimus, ſaith Calvin. But let Hierome hold as he will, we know there is no ſuch thing.

That they may glory in you fleſh] That they pride themſelves in the multitude of their followers, and curry favour with the Jews by gaining many proſelytes.