"Peter was born at Verona, in the year of our Lord 1205, of parents polluted with the Manichaean heresy, but he himself began his lifelong strife against error when he was but a little child. When he was seven years old he went to school, and was asked by his heretic uncle what he learnt there he answered that he had learnt the Christian Creed and neither his father nor his uncle were ever able to shake his constancy in the faith, either by cajolements or threats. When he was a young lad he went to Bologna to study, and there he was called by the Holy Ghost to an higher state of life, and entered the Order of Friars Preachers, at fifteen years of age.
"He was marked by great perfection as a Friar so watchful was he over the purity of his body and soul, that he never felt himself defiled by a mortal sin. He chastened his body by fasting and watching, and ennobled his soul by the contemplation of the things of God. He was constantly busied in works for furthering the salvation of souls and had a peculiar gift of grace for clearly convincing heretics. Such was his power as a preacher, that countless crowds were drawn together to hear him, and many were moved to repentance.
"The faith which was in him burnt so hotly, that he longed to seal his confession with his blood, and oftentimes he earnestly besought from God the grace to do so. It was but a little while before the heretics murdered him, that he foretold, in preaching, his own approaching death. While he was intrusted with the duties of the Holy Inquisition, he was returning from Como to Milan, when an ungodly ruffian assailed him and wounded him once and again in the head with a sword. Peter, to whom these blows were nearly fatal, began with his last breath to recite that Profession of the Faith, to which as a little child he had clung with such manly courage, but the murderer thrust the weapon into his side, and he passed away to receive a Martyr's palm in heaven. It was (the 6th day of April, in) the year of salvation 1252. In the following year, Innocent IV., seeing by how many miracles God had been pleased to glorify him, added his name to the sacred roll of Martyrs."
-Second Nocturn from Mattins