The first says that he, with Carpophorus and Exanthus, were Roman soldiers, members of the legendary Theban Legion, who deserted during the persecution of Christians by Maximian.

[3][4] More likely, he was a Christian missionary sent by Maternus (bishop of Milan) to convert the still pagan area around Lake Como, and there met his death.

Magnus Felix Ennodius describes, in the early sixth century, a tomb at Como containing the relics of the martyr.

The city council, which had been pressured by the populace to bring back the relics, decreed that an annual festival occur on that day, which in succeeding centuries has increased in importance.

The purpose of the festival was extended to include the celebration for the martyrs Felinus and Gratian, thereby uniting their cult to that of Carpophorus and Fidelis.