Do therefore this that we say to thee: We have four men which have a vow on them;(Acts 21:23)

Them take, and purify thyself with them, and be at charges with them, that they may shave their heads: and all may know that those things, whereof they were informed concerning thee, are nothing; but that thou thyself also walkest orderly, and keepest the law.(Acts 21:24)

As touching the Gentiles which believe, we have written and concluded that they observe no such thing, save only that they keep themselves from things offered to idols, and from blood, and from strangled, and from fornication.(Acts 21:25)

Then Paul took the men, and the next day purifying himself with them entered into the temple, to signify the accomplishment of the days of purification, until that an offering should be offered for every one of them.

And when the seven days were almost ended, the Jews which were of Asia, when they saw him in the temple, stirred up all the people, and laid hands on him,(Acts 21:27)

Crying out, Men of Israel, help: This is the man, that teacheth all men every where against the people, and the law, and this place: and further brought Greeks also into the temple, and hath polluted this holy place.(Acts 21:28)

(For they had seen before with him in the city Trophimus an Ephesian, whom they supposed that Paul had brought into the temple.)(Acts 21:29)

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Acts 21:26 - Cross Reference

And unto the Jews I became as a Jew, that I might gain the Jews; to them that are under the law, as under the law, that I might gain them that are under the law; (1 Corinthians 9:20)

And this is the law of the Nazarite, when the days of his separation are fulfilled: he shall be brought unto the door of the tabernacle of the congregation: (Numbers 6:13)

Whereupon certain Jews from Asia found me purified in the temple, neither with multitude, nor with tumult. (Acts 24:18)