Historical Context and Sources
The dates of Sixtus's episcopate are transmitted differently by the early records. The Liberian Catalogue assigns him the years from the consulate of Niger and Apronianus to that of Verus III and Ambibulus (117–126); the Ecclesiastical History of Eusebius places his tenure in 119–128; and the Armenian translation of Eusebius suggests that Telesphorus succeeded him already in 124.
The scholar Richard Adelbert Lipsius sought to reconcile these witnesses, concluding that Sixtus most likely died around 125 after a tenure of about ten years.
The saint is not the subject of a dedicated life in the Orthodox synaxaria: the OCA daily calendar for his feast does not list him, and no entry appears in OrthodoxWiki or in the Mystagogy archive. He is a pre-Nicene Western bishop carried in the pan-Orthodox calendar whose record survives chiefly through Western sources such as Eusebius, the Liberian Catalogue, and the Liber Pontificalis.
Name
In older sources the saint's name appears as "Xystus," derived from the Greek xystos, meaning polished, correct, or shaved. It has been debated whether the later form "Sixtus" also echoes the Latin sextus (sixth), since he was the sixth pope after Peter.
The "Xystus" named in the Canon of the Mass refers to Sixtus II, the later martyr, and not to Sixtus I.
Traditional Ordinances
The Liber Pontificalis attributes three ordinances to Sixtus I. First, that only sacred ministers were permitted to touch the sacred vessels. Second, that bishops summoned to the Holy See were to present Apostolic letters upon returning to their dioceses. Third, that after the Preface in the Mass the priest should recite the Sanctus together with the people.
These attributions come from a later source and are transmitted as tradition rather than as contemporary record.
Relics & Shrines
Following tradition Sixtus was buried near the grave of the Apostle Peter on the Vatican Hill.
His relics were later translated to Alife in Campania, said to have been brought there by Rainulf III, and were housed in a Romanesque crypt in the town. A further distribution of relics is reported under Pope Clement X, who is said to have given them to Cardinal de Retz; these were placed in the Abbey of Saint Michael in Lorraine.
Reflecting the tradition that his relics rest at Alife, he is honored as patron of the Diocese of Alife-Caiazzo and of the Diocese of Anagni-Alatri, and of the Italian towns of Alatri and Alife.
