Then Paul took the men
The four men that had the vow on them; he joined himself to them, and put himself in the same condition, and under a like vow: this he did, not as what he thought himself bound to do in obedience to the law, and much less as necessary to salvation; but to satisfy weak minds, and remove their prejudices, that he might gain them, and be useful to them; and in such a case he would very easily and readily condescend; but when such like things were insisted upon as points of duty, and especially when urged as necessary to salvation, no one more stiffly opposed them:
and the next day purifying himself with them;
that is, not separating himself along with them, from what they were obliged by the vow of the Nazarite, as from drinking of wine and shaving, and from everything that was unclean by the law; for this was now done, but cleansing himself afterwards with them: he
entered into the temple, to signify the accomplishment of the days
of the purification:
the sense is, that when the days of separation were fulfilled, which the four men had vowed, as everyone might vow what time he pleased, he went to the priests in the temple, to signify it to them, that the time of their purification was expiring:
until that an offering should be offered for everyone of them;
as the law directs in ( Numbers 6:13-20 ) when he proposed to pay the charges of it, or at least part of it.