Galatians 2:2-4

Galatians 2:2-4. And communicated unto them that gospel which I preach among the Gentiles, but privately to them which were of reputation, lest by any means I should run, or had run, in vain. But neither Titus, who was with me, being a Greek, was compelled to be circumcised: and that because of false brethren unawares brought in, who came in privily to spy out our liberty which we have in Christ Jesus, that they might bring us into bondage:

There were always some among the Jewish converts who insisted that the Gentiles should come under the seal of the old covenant if they were to be partakers of the blessings of the gospel, but to this Paul would never consent: -