Sixtus III reigned from 31 July, 432 to 19 August, 440, when he died of natural causes. A native Roman, Sixtus was a prominent Roman clergyman for some years before his consecration, going back at least as far as Pope Zosimus. During that time, he was thought to favor the Pelegian heresy occupying North Africa. This is when he began his correspondence with Augustine of Hippo, some letters of which are still extant. Augustine, as I have explained in previous blogs, was against any form of Pelegianism, the teaching that man can make his own salvation and everything is predestined, anyhow.
The new pope was embroiled in a controversy as soon as he was consecrated. A little background is in order. St. John Chrysostom, the fiery orator and stern moralist, had been appointed bishop of Constantinople in 398. He had been educated in Antioch, not such a big deal in itself, but Bishop Theophilus of Alex-andria was trained in Alexandria and the two areas were teaching different theology. Theophilus wanted to get rid of John. In 403, he got his chance when he stacked a regional council with Egyptian bishops who declared John deposed on trumped up charges. Politics being what they were, the emperor Arcadius endorsed the council and exiled John to Armenia. His followers were persecuted also. Some of these got to Rome and asked Pope Innocent (two popes back) for help. Innocent tried. The Italian bishops even got together to declare Theophilus excommunicated. But no one would reopen the case. John died in 407; Theophilus, 412. That is when Cyril took over the bishopric of Alexandria.
In 430, Cyril used his connections with Leo, the archdeacon and advisor to both Celestine and, eventually, Sixtus, to condemn the theological views of Nestorius, the new bishop of Constantinople. Nestorius stressed the separate natures of Jesus, both divine and human. He claimed that this showed that Mary could not be the Mother of God, but only the mother of the human Jesus. The following year, Cyril got permission to have the Council of Ephesus to investigate and depose, if possible, Nestorius. However, the council began before the delegates from Rome and the patriarch of Antioch arrived. The patriarch objected to a number of Cyril's arguments, leading to a formal rift between the churches of Antioch and Alexandria until 433. Sixtus encouraged a formal reconciliation, including a modification of Cyril's original pronouncements.
Sixtus also had to uphold the supremacy of the pope to the Eastern Church. Proclus, another bishop of Constantinople tried to impose a regional synod's decisions on Illyrica (now Serbia, Croatia and parts of Albania). Sixtus had to remind the Illyrian bishops of their obligation to the papal vicar in Thessalonika.
There is nothing, today, which shows Sixtus' papacy as clearly as the architecture of Rome. Thirty-one years after the sack of the Visigoths on Rome, the repair work was not finished. Sixtus completely redid the Liberian Basilica, turning it into the grand church we now know as St. Mary Major, in honor of keeping Mary' title, "Mother of God", as the Council of Ephesus did. The pope also added to the church of St. Lawrence Outside the Walls, making it a basilica. He was awarded gifts from all over the empire which he used to adorn St. Paul's Basilica and the catacombs of Calixtus.
In the late 400s, early 500s, a series of wild stories was published about many of the popes. They were accepted as true for years, but are now known to be fake. St. Sixtus III is revered as a pious man who was a counciliator.
Pope St. Sixtus, pray for us!