John Calvin on Acts 21:14

14. We ceased saying. If they had thought that he ran rashly unto death, they would not have ceased so. Therefore, they yield lest they resist the Holy Spirit, whereby they understand that Paul is governed. For that which they had heard before, by the mouth of Paul, that he was drawn, as it were, by the bands of the Spirit, was quite out of their heads by reason of the sorrow which they had conceived; but when they be taught again that it was the will of God that it should be so, they think it unlawful for them to resist any longer. And with this bridle must all our affections be kept in, that nothing be so bitter, or doleful, or hard, which the will of God may not mitigate and mollify. For so often as any thing which is hard or sharp doth fall out, we give God small honor, unless this cogitation prevail with us, that we must obey him.

Acts 21:15-25

15. And after these days, having taken up our burdens, we went up to Jerusalem. 16. And there came together with us certain of the disciples from Cesarea, bringing with them one Mnason of Cyprus, an old disciple, with whom we should lodge. 17. And when we were come unto Jerusalem, the brethren received us gladly. 18. And on the morrow Paul went in with us unto James; and all the elders were present. 19. Whom after we had saluted, he told by order all things which God had done among the Gentiles by his ministry. 20. But when they had heard, they glorified the Lord, and said to him, Thou seest, brother, how many thousand Jews the be which believe; and they all are earnest followers of the law; 21. And it hath been told them concerning thee, that thou teachest all the Jews which are among the Gentiles to forsake Moses, saying that they must not circumcise their children, nor live according to the customs. 22. What is it then? The multitude must needs come together; for they shall hear that thou art come. 23. Therefore, do this which we say to thee: We have four men which have a vow upon them; 24. Them take, and purify thyself with them, and do cost on them, that they may shave their heads, and that all men may know that those things which they have heard concerning thee are nothing; but that thou thyself also walkest and keepest the law. 25. And as concerning those which among the Gentiles have believed, we have written, decreeing that they observe no such thing, but that they keep themselves from things offered to idols, and from blood, and from that which is strangled, and from fornication.