Paul's arrest in Jerusalem in
Acts 21 was in the spring of AD 57.
In
Acts 18 he came to Corinth in September AD 51. In
Acts 18:11 it says he continued there a year and six months and that he was brought before the judgment seat of Gallio (who became proconsul in July AD 51). In verse 18 of that same chapter it says that he and Priscilla and Aquila sailed 250 miles across the Aegean Sea to Ephesus. This would be on what we call his second missionary journey. It is recorded in verse 18 that while Paul was at Corinth he had "shorn his head in Cenchrea for he had taken a vow."This was a Nazirite vow that Paul had taken several years before he went to Jerusalem in
Acts 21. So we know that the vow in Jerusalem was not his first. We don't know how often Paul may have taken Nazirite vows. The one in Corinth and the one in Jerusalem may have been the only ones he did.