"And when Herod would have brought him forth, the same night Peter was sleeping between two soldiers, bound with two chains: and the keepers before the door kept the prison" (Acts 12:6).
Here is an amazing thing. The apostle Peter is in prison, bound with chains, heavily guarded, probably awaiting execution (his close friend James already had been put to death by Herod), and "prayer was made without ceasing of the church unto God for him" (Acts 12:5).
Yet, here he is, fast asleep! He had been imprisoned at least once before for preaching the gospel, and the Lord had miraculously delivered him then (Acts 5:17-19), so why should he be fearful now? The Lord was still in control, and there was nothing Peter himself could do about the situation, so he simply went to sleep. There are, of course, many situations where a Christian needs to stay alert and watchful. But there are also times when he has done all he can do, and there is nothing to be accomplished by further worrying, so he must leave it in the Lord's hands.
In Peter's case, he was sleeping so soundly that when an angel from God came to deliver him from his "impossible" circumstance, the angel had to smite him on the side (v. 7) to awaken him! In fact, he was still so sleepy that he did not really "come to himself" (v. 11) until the angel left him out on the street alone.
Then, of course, Peter rushed back to the house of Mark's mother, where the church was praying for him (v. 12), to tell them of the amazing answer to their prayers. As with Peter, there are times when we must simply "stand still, and see the salvation of the LORD" (Exodus 14:13), "So that we may boldly say, The Lord is my helper, and I will not fear what man shall do unto me" (Hebrews 13:6). HMM