John Calvin on Acts 21:25

25. And as concerning those which have believed. They add this lest they be thought to go about to take away or call back that liberty which they had granted to the Gentiles, so that they may be burdened with some prejudice. But, in the mean season, they seem to keep the Jews in bondage, from which they set free the Gentiles alone in plain words. I answer, forasmuch as the estate of all was alike, like liberty was granted to both. But there is mention made of the Jews, who were so addicted to their observations and ceremonies, that they would not take to themselves that liberty which they might well challenge. But the apostles did by name provide for the Gentiles, lest the Jews, after their wonted custom, should reject them as profane and unclean, because they were neither circumcised, neither nousled up [educated] in the worship of the law. Moreover, lest I load the paper with a superfluous repetition, let the readers repair unto the fifteenth chapter, (Acts 15:20) where they shall find those things which appertain unto the exposition of this decree.

Acts 21:26-30

26. Then when Paul had taken the men, on the morrow, being purified with them, he entered into the temple, declaring the fulfilling of the days of purification until an offering might be offered for every one of them. 27. And when the seven days were now almost ended, certain Jews of Asia, when they saw him in the temple, moved the people, and laid hands on him, 28. Crying, Men of Israel, help: This is that man, which teacheth all men everywhere against the people, and the law, and this place. Moreover, he hath also brought Grecians into the temple, and hath defiled this holy place. 29. For they had seen Trophimus an Ephesian in the city with him, whom they thought Paul had brought into the temple. 30. And all the whole city was moved, and the people ran together: and when they had caught Paul, they drew him out of the temple: and by and by the doors were shut.