Pope Sixtus I (Greek: Σίξτος), also spelled Xystus, a Roman of Greek descent, was the bishop of Rome from 117 or 119 to his death 126 or 128. He succeeded Alexander I and was in turn succeeded by Telesphorus. His feast is celebrated on 6 April. which is repeated in the Latin translation of his Chronicon. However, the Armenian translation dates Telesphorus’ accession to 124. Eusebius himself begins to show internal inconsistencies for the chronology of this period; Richard Adelbert Lipsius compares the available sources and asserts that Sixtus died between around 125, after a tenure of 10 years.
Like most of his predecessors, Sixtus I was believed to have been buried near Peter's grave on Vatican Hill, although there are differing traditions concerning where his body lies today. In Alife, there is a Romanesque crypt, which houses the relics of Pope Sixtus I, brought there by Rainulf III. Alban Butler (Lives of the Saints, 6 April) states that Clement X gave some of his relics to Cardinal de Retz, who placed them in the Abbey of Saint Michael in Lorraine.
Liturgical codification
Sixtus I instituted several Catholic liturgical and administrative traditions. According to the Liber Pontificalis (ed. Duchesne, I.128), he passed the following three ordinances:
- that none but sacred ministers are allowed to touch the sacred vessels;
- that bishops who have been summoned to the Holy See shall, upon their return, not be received by their diocese except on presenting Apostolic letters;
- that after the Preface in the Mass, the priest shall recite the Sanctus with the people.