Galatians 2:3
But not even Titus, who was with me, was forced to be circumcised, even though he was a Greek.
Acts 16:3
Paul wanted this man to go with him, so he took him and had him circumcised because of the Jews who lived in that region, since everyone knew that Timothy's father was a Greek.
Acts 15:24
Greetings. We have heard that some men, coming from us without instructions from us, have said things to trouble you and have unsettled you.
1 Corinthians 9:20-21
To the Jews I became like a Jew in order to win Jews. To those under the Law I became like a man under the Law, in order to win those under the Law (although I myself am not under the Law).
2 Corinthians 2:13
but my spirit could not find any relief, because I couldn't find Titus, my brother. So I said goodbye to them and went on to Macedonia.
Galatians 5:2-6
Listen! I, Paul, am telling you that if you allow yourselves to be circumcised, the Messiah will be of no benefit to you.