John Calvin on Acts 12:11

11. Then Peter returning to himself. It is word for word, being made in himself, because, being before astonied with a strange and incredible thing, he was, as it were, without himself. But now at length, as it were after a trance, he knoweth that he is delivered from death. His words set down by Luke contain a thanksgiving; for he extolleth with himself the benefit of God which he had tried, [experienced,] and whereof he had tasted, and he doth highly commend it with himself, until he find some other witnesses. He saith that the angel was sent of God, according to the common meaning of the godly, who hold that the angels are appointed to be ministers, to be careful for, and to take charge of their safety; for unless he had been thus persuaded, he would not have spoken of the angel. And yet he doth not commend the angel as the author of the grace, but he ascribeth all the whole praise of the work to God alone, neither do the angels help us to this end, that they may derive unto themselves even the least jot of God’s glory. Whereas he saith that he was delivered out of the hand of Herod, he amplifieth the goodness and benefit of God, by the power of his enemy. To the same end tendeth that which he addeth of the Jews; for the greater the number of the enemies was, the more excellent was the grace of God toward his servant; for it is a great matter that God alone being favorable, the deadly hatred of all the whole world should come to nought.

Acts 12:12-19

12. And, considering, he came into the house of Mary the mother of John, whose surname was Mark; where many were gathered and praying. 13. And when Peter had knocked at the entry-door, a maid came out to hearken, named Rhoda. 14. And when she knew Peter’s voice, she opened not the door for joy, but running in, she told that Peter stood without. 15. But they said to her, Thou art mad. But she affirmed more vehemently that it was so. But they said, It is his angel. 16. But. Peter continued knocking: when they had opened, they saw him, and they were astonished. 17. But after that he had beckoned to them with the hand, that they should hold their peace, he told them how God had brought him out of prison. And he said, Tell James and the brethren these things. And he departed thence, and went into another place. 18. After that it was day, there was no small ado amongst the soldiers, what was become of Peter. 19. And when Herod had sought him, and could not find him, so soon as he knew the matter, he commanded the keepers to be carried away, [executed.]