This fresco depicts the liberation of St. Peter from prison, a miraculous event from Acts of the Apostles (Apostles 12:1-19). The king of the Jews, Herod Agrippa I, had Peter thrown in jail and ordered him to be well guarded. But an angel came at night surrounded by a bright light and freed the apostle, leading him out of prison without the guards noticing, even though they were chained to him. This incident offered Raphael an opportunity to demonstrate his skill as a painter of night scenes. He contrasts the gloom of the dungeon with the blazing light of the angel to great effect, emphasizing the unearthly character of the celestial apparition. The fresco presents three moments in the story: In the center we are shown the prison cell with the angel freeing St. Peter from the shackles that attach him to the two sleeping guards. On the right, he leads the saint carefully by the hand past more sleeping soldiers and out of the prison. On the left, we see the soldiers waking up and agitatedly discussing the inexplicable disappearance of their captive. Within the context of the room, this work attests to the miraculous intervention of God on behalf of the faithful, with a special emphasis on St. Peter as the predecessor of the popes.