John Calvin Commentary Acts 5:33

"But they, when they heard this, were cut to the heart, and minded to slay them." — Acts 5:33 (ASV)

They were cut in sunder. The priests ought to have been thoroughly moved, even if they had hearts of iron, but they burst. From this we gather that no reasons can persuade the reprobate to bring them to the obedience of Christ; for unless God speaks within, the outward doctrine will be able to do nothing else but beat the ears.

The apostles were able to overcome their enemies so effectively that they had nothing to say in response; however, their fury was so untamed and unbridled that they instead went mad. Yet we must also note the force of the word, because although the reprobate are not changed by it to become better, it still pierces their hearts, so that it urges their consciences. For from this springs their fury, because they saw themselves urged by their judge.

They would gladly mock the entire gospel, attempting whatever they can to count it as nothing; but there is in it a certain hidden majesty, which powerfully drives away all their pretense. And especially when they are cited by the sound of the trumpet to appear before the judgment seat of God, then their madness and fury appear.