The Acts 12:4-6

And when he had taken him, he put him in prison, and delivered him to four quaternions of soldiers to guard him; intending after the Passover to bring him forth to the people. Peter therefore was kept in the prison: but prayer was made earnestly of the church unto God for him. And when Herod was about to bring him forth, the same night Peter was sleeping between two soldiers, bound with two chains: and guards before the door kept the prison.