Leo I

Leo was born about the year 390, of an aristocratic Roman family; the Liber Pontificalis records that he was a native of Tuscany and the son of Quintianus. He grew to manhood in a world that was visibly crumbling — the western Empire weakening, its provinces overrun, its cities emptied by war and hunger — and in that ruin he learned to look for the one thing that could not be shaken: the faith of the Apostles.

By 431 he was a deacon of the Roman Church and already known far beyond the city. John Cassian dedicated to him a treatise against Nestorius, written at Leo's own suggestion; and when Cyril of Alexandria appealed to Rome in a jurisdictional dispute with Juvenal of Jerusalem, the letter passed through Leo's hands. His gifts were recognized even by the imperial court: near the end of the pontificate of Sixtus III, the Emperor Valentinian III sent Leo into Gaul to reconcile Aëtius, one of the chief Roman commanders, with the magistrate Albinus — a mission entrusted only to a man of proven wisdom and integrity.

He was still in Gaul on that peacemaking errand when Pope Sixtus III died on 11 August 440. The Roman people, unwilling to have any other, waited for his return, and on 29 September 440 Leo was elected unanimously to the chair of Peter. He did not seek the office; he received it as a burden laid on him by Christ, and he never spoke of himself except as the unworthy heir and vicar of Saint Peter, bound to imitate the Apostle whose authority he held.

His first labors were for the purity of the faith. Learning that at Aquileia former Pelagians were being admitted to communion without renouncing their errors, he censured the practice and ordered a provincial synod at which an unequivocal abjuration must be made. When Manichaeans, likely fleeing the Vandals in Africa, organized secretly in Rome, Leo preached a series of sermons against them in late 443 and worked until, by early 444, he could tell the bishops of Italy that the sect had been rooted out of the city; his contemporary Prosper of Aquitaine records that he exposed the Manichaeans and burned their books. He was equally firm against the Priscillianists: when Bishop Turibius of Astorga wrote in alarm at their spread in Spain, Leo replied on 21 July 447 with an extended treatise examining their false teaching point by point and calling for a general council of the Spanish bishops.

But Leo's care was not only for doctrine. Rome in his day was beset by famine, poverty and floods of refugees, and he threw himself into the works of mercy, organizing relief and binding fasting inseparably to almsgiving, especially at the quarterly Ember days, so that what the Christian denied himself would go to feed the poor. He gathered learned men around him — Prosper of Aquitaine served him in a secretarial capacity — and left behind almost one hundred sermons and one hundred and fifty letters, in which the great mysteries of the faith are opened with a clarity and majesty that have nourished the Church ever since. It was in his time that the name "Pope," once given to any bishop, came to belong to the Bishop of Rome alone.

He labored constantly for the unity of the churches, grounding the primacy of Rome upon the succession from Peter. Called repeatedly to arbitrate in Gaul, he asserted his authority over Hilary of Arles in the appeal of Chelidonius of Besançon, and obtained from Valentinian III the decree of 6 June 445 recognizing the primacy of the Bishop of Rome; afterward, under Hilary's successor Ravennius, he divided the metropolitan rights between Arles and Vienne (450). He wrote to Dioscorus of Alexandria, to the Church in Mauretania Caesariensis in 446 on questions of discipline, insisting that laymen were not to be made bishops, to the bishops of Campania, Picenum and Tuscany in 443, and sharply to the bishops of Sicily in 447 over the proper time of baptism. To Anastasius of Thessalonica, whom he reproached for harshness toward a bishop subject to him, he wrote words that sum up his whole vision of the Church: "The care of the universal Church should converge towards Peter's one seat, and nothing anywhere should be separated from its Head."

His greatest doctrinal service came in the Christological storm. When Eutyches, denying the true human nature of the Son of God, appealed to Rome after his condemnation by Flavian of Constantinople, Leo examined the case and, on receiving full information, sided decisively with Flavian. In 449 his legates carried to the Second Council of Ephesus his famous Tome, a letter to Flavian setting out with luminous precision the faith of the Roman Church. The assembly refused to read it, ignored the legates' protests, and deposed Flavian and Eusebius of Dorylaeum. Leo repudiated all the acts of that "Robber Synod" at a Roman synod in October 449 and demanded of the emperor a true ecumenical council. It met at Chalcedon in 451, the fourth ecumenical council, and there the Tome was read. The bishops cried out: "This is the faith of the fathers, this is the faith of the Apostles… Peter has spoken thus through Leo." The council rejected the error of Eutyches and confessed the union in the one Person of Christ of his two natures, human and divine, without confusion and without separation. Leo firmly refused to confirm the canon that would have given Constantinople an authority practically equal to Rome, but he upheld the council's dogmatic decrees with all his strength, writing letter after letter to bishops and to the imperial family so that the faith of Chalcedon might be received everywhere, especially when, after the accession of the Emperor Leo in 457, some inclined to compromise with the Eutychians.

All his teaching turned on the reality of the Incarnation. If Christ were divine only, he taught, only his divinity would have been crucified, buried and raised, Christians would have no hope of their own resurrection, and the very heart of the faith would be destroyed; because the Word truly took flesh of the Virgin, Mary is truly the Mother of God and our humanity is truly saved. Christ, he insisted, is present still in the Church — in the preaching of the Scriptures and the Tradition, in the sacraments and liturgy, in the life of each believer, and in the councils of the bishops.

When the sword came to Italy, the shepherd went out to meet it. After the indecisive battle of the Catalaunian Plains in 451, Attila the Hun invaded Italy in 452, sacked Aquileia and marched toward Rome. Valentinian III sent three envoys to him — the consul Gennadius Avienus, the former urban prefect Memmius Aemilius Trygetius, and Pope Leo. What was said in that meeting is not recorded, but Attila withdrew and Italy was spared. Prosper of Aquitaine, living at the time, writes that Attila was so impressed by Leo that he turned back; and from that day the Christian people saw in the unarmed bishop who faced the scourge of God the true power that guards the City.

Leo governed for twenty-one years and died on 10 November 461, worn out by labors for the faith, for the unity of the Church, and for the poor of Rome. He was buried at Saint Peter's, and the Church has never ceased to honor him: he is the first of the three popes listed in the Annuario Pontificio with the title "the Great," alongside Gregory I and Nicholas I, and Pope Benedict XV declared him a Doctor of the Church under the title Doctor unitatis Ecclesiae, Doctor of the Church's Unity. His feast is kept on 10 November.

May Saint Leo the Great obtain for us his courage in confessing Christ true God and true man, and may we imitate today his union of fasting with almsgiving, denying ourselves something in order to feed the poor.