Innocent I

What survives best from Innocent I is his correspondence, and it is the correspondence rather than any single decree that made his reign matter. Writing to Victricius of Rouen, to Exsuperius of Toulouse, to the bishops of Spain and, most fully, to Decentius of Gubbio in 416, he set out a consistent position: that every church of the West traces its foundation to Peter or to men Peter sent, that Roman usage in liturgy and discipline is therefore the norm rather than one custom among several, and that any case of major importance should be referred to Rome before it is settled locally.

The claim was not invented by him. Damasus and Siricius had asserted Roman authority before, and Innocent was working within an argument the see had been developing for decades. What he added was consistency and reach, applying the principle to concrete questions put to him by distant bishops, so that the answers became precedents. The letter to Decentius goes down to details of the sign of peace, confirmation and the anointing of the sick, treating divergence from Roman practice as an irregularity rather than a local tradition.

His pontificate coincided with the collapse of Roman security in Italy. He was at Ravenna as part of an embassy negotiating with the emperor Honorius when Alaric took the city in August 410, and he returned to a Rome that had been sacked for the first time in eight hundred years. The disaster gave force to the argument, made at length elsewhere by Augustine, that the church's authority did not rest on the fortunes of the empire, and it left the bishop of Rome as the most stable institution in a city whose civil order had failed.

Two disputes dominated Innocent I's dealings beyond Italy. The first came from the East. John Chrysostom, the ascetic preacher made archbishop of Constantinople, was deposed and exiled after the Synod of the Oak in 403 in a proceeding driven by his enemies at court and by Theophilus of Alexandria. Innocent refused to recognize the deposition, wrote in Chrysostom's defence, sent a legation that was turned back, and broke communion with Constantinople, Alexandria and Antioch over the affair. Chrysostom died in exile in 407, and the breach was healed only when his name was restored to the diptychs years afterwards.

The second came from Africa. Pelagius and his follower Caelestius taught that human beings can choose the good without a prior and interior gift of grace, a position Augustine read as emptying baptism and the cross of their necessity. African councils at Carthage and Milevis condemned the two in 416 and wrote to Rome asking for confirmation. Innocent replied in January 417 upholding the condemnations, and Augustine, preaching at Carthage that autumn, told his congregation that two councils had written to the apostolic see, the replies had come back, and the case was finished.

Augustine's actual words were causa finita est, the case is finished. The familiar tag Roma locuta est, causa finita est, Rome has spoken, the case is closed, is a later condensation that does not appear in his sermon, and it carries a stronger sense of Roman finality than his argument allows: Augustine was pointing to the agreement of councils and see together. The distinction matters, because the sentence has been quoted on both sides of the question of papal authority for fifteen hundred years. Innocent died within months, and his successor Zosimus promptly reopened the Pelagian case.