Acts 21:24
Take these men and observe the ceremony of purification with them, pay their expenses so they can shave their heads [i.e., to signify that they are making a vow] and [then] everyone will know that there is no truth in what people have been told about you, but that you, too, are living properly and observing the law of Moses.
Acts 18:18
After this [incident] Paul remained [in Corinth] for some time before leaving the brothers and sailing for Syria with Priscilla and Aquila. Paul shaved his head while in Cenchrea as part of a vow he had taken.
Luke 17:10
So, you too, after you have done everything you were told to, should say, 'We are unworthy slaves. We have done [only] what we were supposed to do.'"
Acts 21:26
Then Paul took the men and the next day he observed the ceremony of purification with them. Then he went into the Temple, declaring [to the priest] when he would fulfill the [required] days of the purification [ceremony] and [be ready] for the sacrifices to be offered for each of them.
Ephesians 1:6
so that we would praise His glorious, unearned favor, which was freely given to us through the One whom God loved [i.e., Christ].