Paul the Apostle was a Keeper of the Law of Moses

It is often believed that Paul the Apostle teaches against keeping the law of Moses.

This is a false rumor.

The leaders of the Jerusalem church called it a false rumor, urged Paul to prove it was a false rumor, and urged Paul to prove that he himself walked according to the law.

Paul followed their advice, and was arrested while doing so, because some from outside of Jerusalem weren't paying attention, and still believed the false rumor.

Don't be like those from outside of Jerusalem, believing a false rumor about Paul.

Note that Paul *did* teach against keeping the law of Moses as a way of being made righteous. He taught very strongly this message. But he never taught against keeping the law of Moses as a voluntary, Jewish-thing to do, including taking Nazirite vows, undergoing Temple-based purification rituals, offering animal sacrifices to end a Nazirite vow (after a seven-day waiting period), claiming his innocence in accord with his being (present-tense) a Pharisee, and worshiping God in the Jewish temple wherein worship activities included choirs and incense and robes and instrumental music.

You can get more detail from Acts 18:18, Acts 21:17, to the end of Acts.