12 The Apostle Peter also gives you an example of either case. For when Herod sought him and took him, he was put into prison. For the servant of God had not got away, but stood firm without a thought of fear. The Church prayed for him, but the Apostle slept in prison, a proof that he was not in fear. An angel was sent to rouse him as he slept, by whom Peter was led forth out of prison, and escaped death for a time.
Source: Sermon against Auxentius (New Advent)