Catholic Encyclopedia – Pope Saint Sixtus III

detail of a bas-relief portrait medallion of Pope Saint Sixtus III, date and artist unknown; Saint Peter's Basilica, Rome, ItalyArticle

(XYSTUS). Consecrated 31 July 432; died 440. Previous to his accession he was prominent among the Roman clergy and in correspondence with Saint Augustine. He reigned during the Nestorian and Pelagian controversies, and it was probably owing to his conciliatory disposition that he was falsely accused of leanings towards these heresies. As pope he approved the Acts of the Council of Ephesus and endeavoured to restore peace between Cyril of Alexandria and John of Antioch. In the Pelagian controversy he frustrated the attempt of Julian of Eclanum to be readmitted to communion with the Catholic Church. He defended the pope’s right of supremacy over Illyricum against the local bishops and the ambitious designs of Proclus of Constantinople. At Rome he restored the Basilica of Liberius, now known as Saint Mary Major, enlarged the Basilica of Saint Lawrence-Without-the-Walls, and obtained precious gifts from the Emperor Valentinian III for Saint Peter’s and the Lateran Basilica. The work which asserts that the consul Bassus accused him of crime is a forgery. He is the author of eight letters, but he did not write the works “On Riches”, “On False Teachers”, and “On Chastity” (“De divitiis”, “De malis doctoribus”, “De castitate”) attributed to him. His feast is kept on 28 March.

MLA Citation

  • Nicholas Aloysius Weber. “Pope Saint Sixtus III”. Catholic Encyclopedia, 1913. CatholicSaints.Info. 11 August 2018. Web. 18 September 2021. <>