For some reason, probably in the midst of his work at Corinth, Paul took on himself the Nazarite vow. This could only be terminated by his going up to Jerusalem to offer up the hair which till then was to be left uncut. But it seems to have been allowable for persons at a distance to cut the hair, which was to be brought up to Jerusalem, where the ceremony was completed. This Paul did at Cenchrea just before setting out on his voyage into Syria (
Acts 18:18).
On another occasion (
Acts 21:23-26), at the feast of Pentecost, Paul took on himself again the Nazarite vow.