According to the legend, the magician Simon Magus wanted to prove that his powers were superior to those of the Apostles. To do this, he levitated himself above the Forum. St Peter fell to his knees in the crowd and prayed that God would humble Simon Magus, which He did with a vengeance - Simon immediately fell to his death. These stones were originally venerated in situ by the Via Sacra, and later brought into the church for safe-keeping.