SIXTUS III, POPE, ST.

Pontificate: July 31, 432 to Aug. 19, 440. This pope was a Roman, the son of Xystus, and a priest at the time of his election. He was well known to (St.) augustine and seems to have sympathized with pelagius until the issuance of the Tractoria of Pope zosimus. Sixtus then abandoned Pelagius and was reminded of the limits of prudence and charity by Augustine.

Sixtus encouraged the negotiations, following the Council of ephesus (431), between cyril of alexan dria and john of antioch, who finally reached agreement regarding the two natures in Christ; the pope wrote to congratulate them (433). During his pontificate, friendly relations between Rome, Constantinople, and Alexandria had all but liquidated the Nestorian problem, until proclus succeeded Maximian as bishop of Constantinople and attempted to impose the decisions of a Constantinopolitan council on the bishops of Illyricum. Sixtus wrote to Bp. Anastasius of Thessalonica confirming his office as papal vicar and warning the Illyrian bishops against the jurisdictional encroachments of Proclus. At the same time, he requested Proclus not to tolerate appeals to Constantinople from the Illyrian bishops. On the other hand, when Iddua, the bishop of Smyrna, appealed to Rome against a sentence rendered by Proclus as metropolitan of Asia Minor, the pope refused to interfere, thus indicating his determination to uphold the system of vicariates. The matter remained a thorny one in Roman-Constantinopolitan relations.

Probably relying on the memory of old sympathies, the exiled Pelagian, julian of eclanum, attempted to persuade Sixtus to allow him to return to his see in Italy (439), but the pope was warned against such a gesture by the deacon (later pope) Leo.

The name of Sixtus III is linked with several of Rome's outstanding churches and monuments, and modern scholars speak of a Sixtine Renaissance. He rebuilt the Lateran baptistery, giving it the form that it has retained ever since: the inscription on the marble beams around the font extols grace and the theology of baptism to mark the Church's triumph over the heresy of Pelagius. His most important undertaking was a complete reconstruction of the Liberian Basilica of Saint Mary Major on the Esquiline Hill and its dedication to the Virgin Mary (the first, and for many years the only, church to be so dedicated in Rome). Its majestic mosaics commemorated the triumph of the Church over the heresy of Nestorius.

A second basilica was joined to the Constantinian church of St. Lawrence Outside the Walls. The Roman Emperor valentinian iii was persuaded to contribute costly silver and gold ornaments to the basilicas of St. Peter, St. Paul, and the Lateran to replace what had been carried off by the Visigoths.

The first monastery in Rome was established at St. Sebastian's to ensure the daily recitation of the Divine Office, and in the papal crypt at St. Callistus the pope erected an important inscription or plaque on which were listed the names of the bishops and martyrs buried there. Sixtus himself was buried in St. Lawrence, although the exact location of his tomb is unknown. Ado of Sens was the first to include him in his ninth-century version of the Roman martyrology under the date of March 28.

Feast: March 28.

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[j. chapin]