Acts 21:26
Then Paul joined the men and went through the rites of purification with them and the next day went to the Temple to give notice of the time when, upon the offering of the sacrifice for each one of them, their days of purification would be over.
Acts 24:18
I had undergone the rites of purification and was occupied with these matters when they found me in the Temple, with no crowd or disturbance at all. But there were some Jews from Asia
Acts 21:24
Join them, undergo the rites of purification with them, and pay their expenses so that they can have their heads shaved. Then everybody will understand that there is no truth in the stories about you, but that you yourself observe the Law.
1 Corinthians 9:20
To the Jews I have become like a Jew, to win Jews over; to men under the Law I have become like a man under the Law, though I am not myself under the Law, so as to win over those who are under the Law.