Cross reference
Galatians 2:3
3 But not even Titus who was with me, being a Greek, was made to undergo circumcision:
Acts 16:3
3 Paul had a desire for him to go with him, and he gave him circumcision because of the Jews who were in those parts: for they all had knowledge that his father was a Greek.
Galatians 5:2-6
2 See, I Paul say to you, that if you undergo circumcision, Christ will be of no use to you.
3 Yes, I give witness again to every man who undergoes circumcision, that he will have to keep all the law.
4 You are cut off from Christ, you who would have righteousness by the law; you are turned away from grace.
5 For we through the Spirit by faith are waiting for the hope of righteousness.
6 Because in Christ Jesus, having circumcision or not having circumcision are equally of no profit; but only faith working through love.
1 Corinthians 9:20-21
20 And to the Jews I was as a Jew, so that I might give the good news to them; to those under the law I was the same, not as being myself under the law, but so that I might give the good news to those under the law.
21 To those without the law I was as one without the law, not as being without law to God, but as under law to Christ, so that I might give the good news to those without the law.
Acts 15:24
24 Because we have knowledge that some who went from us have been troubling you with their words, putting your souls in doubt; to whom we gave no such order;
2 Corinthians 2:13
13 I had no rest in my spirit because Titus my brother was not there: so I went away from them, and came into Macedonia.