Acts 12:3-7

³And seeing that it was pleasing to the Jews, he went on to take Peter also: (and they were the days of unleavened bread:)

⁴whom having seized he put in prison, having delivered him to four quaternions of soldiers to keep, purposing after the passover to bring him out to the people.

⁵Peter therefore was kept in the prison; but unceasing prayer was made by the assembly to God concerning him.

⁶And when Herod was going to bring him forth, that night Peter was sleeping between two soldiers, bound with two chains, and guards before the door kept the prison.

⁷And lo, an angel of the Lord came there, and a light shone in the prison: and having smitten the side of Peter, he roused him up, saying, Rise up quickly. And his chains fell off his hands.