On June 2, the Catholic Church remembers two fourth-century martyrs, Saints Marcellinus and Peter, who were highly venerated after the discovery of their tomb and the conversion of their executioner.
Though we know very little about these two martyrs under Diocletian, there is no question that the early church venerated them. Evidence of the respect in which they were held are the basilica Constantine built over their tombs and the presence of their names in the first eucharistic prayer.
Pope St. Damasus I, who was himself a great devotee of the Church's saints during his life,
composed an epitaph to mark the tombs of the two martyrs. The source of his knowledge, he
said, was the executioner himself, who had subsequently repented and joined the Catholic Church. Marcellinus, a priest, and Peter, an exorcist, died in the year 304. According to a legendary account of their martyrdom, the two Romans saw their imprisonment as just one more opportunity to evangelize and managed to convert their jailer and his family. The legend also says that they were beheaded in the forest so that other Christians wouldn't have a chance to bury and venerate their bodies. Two women found the bodies, however, and had them properly buried.
The feast of these two martyrs was included in the Roman calendar of saints by Pope Vigilius in 555.