 It houses a 13th-century "Crucifix" on panel, frescoes by Buonamico Buffalmacco and a "Madonna with Saints" by Turino Vanni (14th century), but most of all a 2nd-century Roman sarcophagus used as medieval tomb.The relief on this sarcophagus was used as a model by both Nicola Pisano and his pupil Arnolfo di Cambio 

Behind the church is located the St. Agatha Chapel, a small Romanesque chapel built around 1063 by the monks.It was built to celebrate the conquest of the city of Palermo in that year and dedicated to the Saint, who was martyred in Sicily.