Here, Ter Brugghen has painted the biblical story of St Peter’s liberation from prison. The angel is waking him and pointing upwards, as if to say that God has sent him. St Peter looks alarmed and folds his chained hands.
Ter Brugghen created a very powerful painting with strong contrasts between light and dark, and expressive facial expressions. He also showed the two figures very close up. Ter Brugghen had copied this style from the Italian painter Caravaggio, whose work he had seen in Rome.