formerly 6 August
Philosopher and adult convert to Christianity. Deacon in Rome. Pope for less than a year.
He dealt with the controversy concerning Baptism by heretics. He believed that anyone who was baptised with a desire to be a Christian, even if the Baptism was performed by a heretic, was truly baptised into the faith, and that the validity of his faith was based on his own desire and actions, not the errors of the person who performed the sacrament.
While celebrating Mass at the tomb of Saint Callistus, he was arrested as part of the persecutions of Valerian. He was beheaded with six deacons and sub-deacons, and was buried in the same catacomb where he had been celebrating Mass when he was arrested; his name occurs in the prayer Communicantes in the Canon of the Mass. Martyr.
30 August 257
beheaded on 6 August 258 in a cemetery on the Appian Way, Rome, Italy