SISTUS I, POPE, saint. — Sixth successor of the Apostles, his pontificate can be approximately placed between 115 and 125. Florus was the first to include him in his Martyrology, from which he passed into the Roman Martyrology, in which he is commemorated on April 6 as a martyr, though this quality is not attested by ancient ecclesiastical sources.
The author of the Liber Pontificalis calls him a Roman, son of a certain Pastor. The chronology of his pontificate is uncertain, as indeed is that of the popes of the first two centuries. According to Eusebius (Hist. eccl., IV, 5), he succeeded Alexander and died in 128–29 after about ten years of episcopate; according to the Liberian Catalogue, however, he died in 126. He is credited with a decree establishing that only ministers could touch the sacred vessels and that the people, in liturgical assemblies, should sing the Sanctus after the priest’s intonation. He was buried in the Vatican.