Giovan Battista Moroni was commissioned to paint the
altarpiece for the Dominican nuns of the Matris Domini monastery in Bergamo. The painter here
faithfully adheres to the long iconographic tradition of the martyrdom of Saint
Peter of Verona, a Dominican sent by Innocent IV to convert the Cathars of
Lombardy and who was assassinated in 1252 by a group of heretics while crossing
Barlassina wood near Como. His martyrdom is meticulously recounted and the painting
depicts the moment when the saint, about to be struck, recites the
"Credo".