He is recapping the words of those who are trying to keep the LAW of circumcision, as a “good showing in the flesh.”
They worked to bring the Galatian Christians from a Gentile background under circumcision because it would be a good showing for them.
i. It doesn’t really mean anything, but it looks good.
ii. Paul here referred to the legalistic Christians among the Galatians and wrote frankly about their motive.
Due to the traditions, if they claimed salvation under Christ, and not the law, they feared persecution.