Pope Saint Leo I (the Great)

(Reigned 440-61).

Place and date of birth unknown; died 10 November, 461. Leo's pontificate, next

to that of St. Gregory I, is the most significant and important in Christian

antiquity. At a time when the Church was experiencing the greatest obstacles to

her progress in consequence of the hastening disintegration of the Western

Empire, while the Orient was profoundly agitated over dogmatic controversies,

this great pope, with far-seeing sagacity and powerful hand, guided the destiny of

the Roman and Universal Church. According to the "Liber Pontificalis" (ed.

Mommsen, I, 101 sqq., ed. Duchesne, I, 238 sqq.), Leo was a native of Tuscany

and his father's name was Quintianus. Our earliest certain historical information

about Leo reveals him a deacon of the Roman Church under Pope Celestine I

(422-32). Even during this period he was known outside of Rome, and had some

relations with Gaul, since Cassianus in 430 or 431 wrote at Leo's suggestion his

work "De Incarnatione Domini contra Nestorium" (Migne, P.L., L, 9 sqq.),

prefacing it with a letter of dedication to Leo. About this time Cyril of Alexandria

appealed to Rome against the pretensions of Bishop Juvenal of Jerusalem. From

an assertion of Leo's in a letter of later date (ep. cxvi, ed. Ballerini, I, 1212; II,

1528), it is not very clear whether Cyril wrote to him in the capacity of Roman

deacon, or to Pope Celestine. During the pontificate of Sixtus III (422-40), Leo

was sent to Gaul by Emperor Valentinian III to settle a dispute and bring about a

reconciliation between Aëtius, the chief military commander of the province, and

the chief magistrate, Albinus. This commission is a proof of the great confidence

placed in the clever and able deacon by the Imperial Court. Sixtus III died on 19

August, 440, while Leo was in Gaul, and the latter was chosen his successor.

Returning to Rome, Leo was consecrated on 29 September of the same year,

and governed the Roman Church for the next twenty-one years.

Leo's chief aim was to sustain the unity of the Church. Not long after his

elevation to the Chair of Peter, he saw himself compelled to combat energetically

the heresies which seriously threatened church unity even in the West. Leo had

ascertained through Bishop Septimus of Altinum, that in Aquileia priests,

deacons, and clerics, who had been adherents of Pelagius, were admitted to

communion without an explicit abjuration of their heresy. The pope sharply

censured this procedure, and directed that a provincial synod should be

assembled in Aquileia, at which such persons were to be required to abjure

Pelagianism publicly and to subscribe to an unequivocal confession of Faith

(epp. i and ii). This zealous pastor waged war even more strenuously against

Manichæism, inasmuch as its adherents, who had been driven from Africa by the

Vandals, had settled in Rome, and had succeeded in establishing a secret

Manichæan community there. The pope ordered the faithful to point out these

heretics to the priests, and in 443, together with the senators and presbyters,

conducted in person an investigation, in the course of which the leaders of the

community were examined. In several sermons he emphatically warned the

Christians of Rome to be on their guard against this reprehensible heresy, and

repeatedly charged them to give information about its followers, their dwellings,

acquaintances, and rendezvous (Sermo ix, 4, xvi, 4; xxiv, 4; xxxiv, 4 sq.; xlii, 4

sq.; lxxvi, 6). A number of Manichæans in Rome were converted and admitted to

confession; others, who remained obdurate, were in obedience to imperial

decrees banished from Rome by the civil magistrates. On 30 January, 444, the

pope sent a letter to all the bishops of Italy, to which he appended the

documents containing his proceedings against the Manichæans in Rome, and

warned them to be on their guard and to take action against the followers of the

sect (ep. vii). On 19 June, 445, Emperor Valentinian III issued, doubtless at the

pope's instigation, a stern edict in which he estasblished seven punishments for

the Manichæans ("Epist. Leonis", ed. Ballerini, I, 626; ep. viii inter Leon. ep).

Prosper of Aquitaine states in his "Chronicle" (ad an. 447; "Mon. Germ. hist.

Auct. antiquissimi", IX, I, 341 sqq.) that, in consequence of Leo's energetic

measures, the Manichæans were also driven out of the provinces, and even

Oriental bishops emulated the pope's example in regard to this sect. In Spain the

heresy of Priscillianism still survived, and for some time had been attracting fresh

adherents. Bishop Turibius of Astorga became cognizant of this, and by

extensive journeys collected minute information about the condition of the

churches and the spread of Priscillianism. He compiled the errors of the heresy,

wrote a refutation of the same, and sent these documents to several African

bishops. He also sent a copy to the pope, whereupon the latter sent a lengthy

letter to Turibius (ep. xv) in refutation of the errors of the Priscillianists. Leo at the

same time ordered that a council of bishops belonging to the neighbouring

provinces should be convened to institute a rigid enquiry, with the object of

determining whether any of the bishops had become tainted with the poison of

this heresy. Should any such be discovered, they were to be excommunicated

without hesitation. The pope also addressed a similar letter to the bishops of the

Spanish provinces, notifying them that a universal synod of all the chief pastors

was to be summoned; if this should be found to be impossible, the bishops of

Galicia at least should be assembled. These two synods were in fact held in

Spain to deal with the points at issue "Hefele, "Konziliengesch." II, 2nd ed., pp.

306 sqq.).

The greatly disorganized ecclesiastical condition of certain countries, resulting

from national migrations, demanded closer bonds between their episcopate and

Rome for the better promotion of ecclesiastical life. Leo, with this object in view,

determined to make use of the papal vicariate of the bishops of Arles for the

province of Gaul for the creation of a centre for the Gallican episcopate in

immediate union with Rome. In the beginning his efforts were greatly hampered

by his conflict with St. Hilary, then Bishop of Arles. Even earlier, conflicts had

arisen relative to the vicariate of the bishops of Arles and its privileges. Hilary

made excessive use of his authority over other ecclesiastical provinces, and

claimed that all bishops should be consecrated by him, instead of by their own

metropolitan. When, for example, the complaint was raised that Bishop

Celidonius of Besançon had been consecrated in violation of the canons–the

grounds alleged being that he had, as a layman, married a widow, and, as a

public officer, had given his consent to a death sentence–Hilary deposed him,

and consecrated Importunus as his successor. Celidonius thereupon appealed to

the pope and set out in person for Rome. About the same time Hilary, as if the

see concerned had been vacant, consecrated another bishop to take the place of

a certain Bishop Projectus, who was ill. Projectus recovered, however, and he

too laid a complaint at Rome about the action of the Bishop of Arles. Hilary then

went himself to Rome to justify his proceedings. The pope assembled a Roman

synod (about 445) and, when the complaints brought against Celidonius could

not be verified, reinstated the latter in his see. Projectus also received his

bishopric again. Hilary returned to Arles before the synod was over; the pope

deprived him of jurisdiction over the other Gallic provinces and of metropolitan

rights over the province of Vienne, only allowing him to retain his Diocese of

Arles.

These decisions were disclosed by Leo in a letter to the bishops of the Province

of Vienne (ep. x). At the same time he sent them an edict of Valentinian III of 8

July, 445, in which the pope's measures in regard to St. Hilary were supported,

and the primacy of the Bishop of Rome over the whole Church solemnly

recognized "Epist. Leonis," ed. Ballerini, I, 642). On his return to his bishopric

Hilary sought a reconciliation with the pope. After this there arose no further

difficulties between these two saintly men and, after his death in 449, Hilary was

declared by Leo as "beatæ memoriæ". To Bishop Ravennius, St. Hilary's

successor in the see of Arles, and the bishops of that province, Leo addressed

most cordial letters in 449 on the election of the new metropolitan (epp. xl, xli).

When Ravennius consecrated a little later a new bishop to take the place of the

deceased Bishop of Vaison, the Archbishop of Vienne, who was then in Rome,

took exception to this action. The bishops of the province of Arles then wrote a

joint letter to the pope, in which they begged him to restore to Ravennius the

rights of which his predecessor Hilary had been deprived (ep. lxv inter ep.

Leonis). In his reply dated 5 May, 450 (ep. lxvi), Leo acceded to their request.

The Archbishop of Vienne was to retain only the suffragan Bishoprics of Valence,

Tarentaise, Geneva, and Grenoble; all the other sees in the Province of Vienne

were made subject to the Archbishop of Arles, who also became again the

mediator between the Holy See and the whole Gallic episcopate. Leo transmitted

to Ravennius (ep. lxvii), for communication to the other Gallican bishops, his

celebrated letter to Flavian of Constantinople on the Incarnation. Ravennius

thereupon convened a synod, at which forty-four chief pastors assembled. In their

synodal letter of 451, they affirm that they accept the pope's letter as a symbol of

faith (ep. xxix inter ep. Leonis). In his answer Leo speaks further of the

condemnation of Nestorius (ep. cii). The Vicariate of Arles for a long time

retained the position Leo had accorded it. Another papal vicariate was that of the

bishops of Thessalonica, whose jurisdiction extended over Illyria. The special

duty of this vicariate was to protect the rights of the Holy See over the district of

Eastern Illyria, which belonged to the Eastern Empire. Leo bestowed the vicariate

upon Bishop Anastasius of Thessalonica, just as Pope Siricius had formerly

entrusted it to Bishop Anysius. The vicar was to consecrate the metropolitans, to

assemble in a synod all bishops of the Province of Eastern Illyria, to oversee their

administration of their office; but the most important matters were to be

submitted to Rome (epp. v, vi, xiii). But Anastasius of Thessalonica used his

authority in an arbitrary and despotic manner, so much so that he was severely

reproved by Leo, who sent him fuller directions for the exercise of his office (ep.

xiv).

In Leo's conception of his duties as supreme pastor, the maintenance of strict

ecclesiastical discipline occupied a prominent place. This was particularly

important at a time when the continual ravages of the barbarians were introducing

disorder into all conditions of life, and the rules of morality were being seriously

violated. Leo used his utmost energy in maintining this discipline, insisted on the

exact observance of the ecclesiastical precepts, and did not hesitate to rebuke

when necessary. Letters (ep. xvii) relative to these and other matters were sent

to the different bishops of the Western Empire–ee.g., to the bishops of the Italian

provinces (epp. iv, xix, clxvi, clxviii), and to those of Sicily, who had tolerated

deviations from the Roman Liturgy in the administration of Baptism (ep. xvi), and

concerning other matters (ep. xvii). A very important disciplinary decree was sent

to bishop Rusticus of Narbonne (ep. clxvii). Owing to the dominion of the Vandals

in Latin North Africa, the position of the Church there had become extremely

gloomy. Leo sent the Roman priest Potentius thither to inform himself about the

exact condition, and to forward a report to Rome. On receiving this Leo sent a

letter of detailed instructions to the episcopate of the province about the

adjustment of numerous ecclesiastical and disciplinary questions (ep. xii). Leo

also sent a letter to Dioscurus of Alexandria on 21 July, 445, urging him to the

strict observance of the canons and discipline of the Roman Church (ep. ix). The

primacy of the Roman Church was thus manifested under this pope in the most

various and distinct ways. But it was especially in his interposition in the

confusion of the Christological quarrels, which then so profoundly agitated

Eastern Christendom, that Leo most brilliantly revealed himself the wise, learned,

and energetic shepherd of the Church (see MONOPHYSITISM). From his first letter

on this subject, written to Eutyches on 1 June, 448 (ep. xx), to his last letter

written to the new orthodox Patriarch of Alexandria, Timotheus Salophaciolus, on

18 August, 460 (ep. clxxi), we cannot but admire the clear, positive, and

systematic manner in which Leo, fortified by the primacy of the Holy See, took

part in this difficult entanglement. For particulars refer to the articles: EUTYCHES ;

SAINT FLAVIAN; ROBBER COUNCIL OF EPHESUS.

Eutyches appealed to the pope after he had been excommunicated by Flavian,

Patriarch of Constantinople, on account of his Monophysite views. The pope,

after investigating the disputed question, sent his sublime dogmatic letter to

Flavian (ep. xxviii), concisely setting forth and confirming the doctrine of the

Incarnation, and the union of the Divine and human natures in the one Person of

Christ . In 449 the council, which was designated by Leo as the "Robber Synod",

was held. Flavian and other powerful prelates of the East appealed to the pope.

The latter sent urgent letters to Constantinople, particularly to Emperor

Theodosius II and Empress Pulcheria, urging them to convene a general council

in order to restore peace to the Church. To the same end he used his influence

with the Western emperor, Valentinian III, and his mother Galla Placidia,

especially during their visit to Rome in 450. This general council was held in

Chalcedon in 451 under Marcian, the successor of Theodosius. It solemnly

accepted Leo's dogmatical epistle to Flavian as an expression of the Catholic

Faith concerning the Person of Christ. The pope confirmed the decrees of the

Council after eliminating the canon, which elevated the Patriarchate of

Constantinople, while diminishing the rights of the ancient Oriental patriarchs. On

21 March, 453, Leo issued a circular letter confirming his dogmatic definition (ep.

cxiv). Through the mediation of Bishop Julian of Cos, who was at that time the

papal ambassador in Constantinople, the pope tried to protect further

ecclesiastical interests in the Orient. He persuaded the new Emperor of

Constantinople, Leo I, to remove the heretical and irregular patriarch, Timotheus

Ailurus, from the See of Alexandria. A new and orthodox patriarch, Timotheus

Salophaciolus, was chosen to fill his place, and received the congratulations of

the pope in the last letter which Leo ever sent to the Orient.

In his far-reaching pastoral care of the Universal Church, in the West and in the

East, the pope never neglected the domestic interests of the Church at Rome.

When Northern Italy had been devastated by Attila Leo by a personal encounter

with the King of the Huns prevented him from marching upon Rome. At the

emperor's wish, Leo, accompanied by the Consul Avienus and the Prefect

Trigetius, went in 452 to Upper Italy, and met Attila at Mincio in the vicinity of

Mantua, obtaining from him the promise that he would withdraw from Italy and

negotiate peace with the emperor. The pope also succeeded in obtaining another

great favour for the inhabitants of Rome. When in 455 the city was captured by

the Vandals under Genseric, although for a fortnight the town had been

plundered, Leo's intercession obtained a promise that the city should not be

injured and that the lives of the inhabitants should be spared. These incidents

show the high moral authority enjoyed by the pope, manifested even in temporal

affairs. Leo was always on terms of intimacy with the Western Imperial Court. In

450 Emperor Valentinian III visited Rome, accompanied by his wife Eudoxia and

his mother Galla Placidia. On the feast of Cathedra Petri (22 February), the

Imperial family with their brilliant retinue took part in the solemn services at St.

Peter's, upon which occasion the pope delivered an impressive sermon. Leo was

also active in building and restoring churches. He built a basilica over the grave of

Pope Cornelius in the Via Appia. The roof of St. Paul's without the Walls having

been destroyed by lightning, he had it replaced, and undertook other

improvements in the basilica. He persuaded Empress Galla Placidia, as seen

from the inscription, to have executed the great mosaic of the Arch of Triumph,

which has survived to our day. Leo also restored St. Peter's on the Vatican.

During his pontificate a pious Roman lady, named Demetria, erected on her

property on the Via Appia a basilica in honour of St. Stephen, the ruins of which

have been excavated.

Leo was no less active in the spiritual elevation of the Roman congregations, and

his sermons, of which ninety-six genuine examples have been preserved, are

remarkable for their profundity, clearness of diction, and elevated style. The first

five of these, which were delivered on the anniversaries ofh his consecration,

manifest his lofty conception of the dignity of his office, as well as his thorough

conviction of the primacy of the Bishop of Rome, shown forth in so outspoken

and decisive a manner by his whole activity as supreme pastor. Of his letters,

which are of great importance for church history, 143 have come down to us: we

also possess thirty which were sent to him. The so-called "Sacramentarium

Leonianum" is a collection of orations and prefaces of the Mass, prepared in the

second half of the sixth century. Leo died on 10 November, 461, and was buried

in the vestibule of St. Peter's on the Vatican. In 688 Pope Sergius had his

remains transferred to the basilica itself, and a special altar erected over them.

They rest to-day in St. Peter's, beneath the altar specially dedicated to St. Leo.

In 1754 Benedict XIV exalted him to the dignity of Doctor of the Church (doctor

ecclesiæ). In the Latin Church the feast day of the great pope is held on 11 April,

and in the Eastern Church on 18 February.

BIBLIOGRAPHY. Leonis Opera omnia, ed. ARDICINIO DELLA PORTA, (Rome, 1470); ed.

QUESNEL (2 vols., Paris, 1675); edd. PETRUS AND HIERONYMUS BALLERINI (2 vols., Venice,

1753-7); ed. in P.L., LIV-VI; AMELLI, S. Leone dMagno e l'Oriente (Rome, 1886), 361-8; JAFFÉ

Regesta Rom. Pont., 2nd ed., I, 58 sqq.; VON NOSTITZRIENECK, Die Briefe Papst Leos I. im

Codex Monacen. 14540 in Historisches Jahrbuch (1897), 117- 33; IDEM, Die päpstlichen Urbanden

f252;r Thessalonike und deren Kritik durch Prof. Friedrich in Zeitsch. für kath. Theologie (1897),

1-50. Translation of letters and sermons given in FELTOE, A select Library of Nicene and

Post-Nicene Fathers, XIId (2nd series, New York, 1896); Sacramentarium Leonianum, ed. FELTOE

(Cambridge, 1897). Concerning the Sacramentarium, cf. DUCHESNE, Christian Worship; its origin

and evolution (London, 1903), 135 sqq.; and PROBST, Die ältesten römischen Sacramentarien und

Ordines erklärt (Münster, 1892).;–Liber Pontificalis, ed. DUCHESNE, I, 238 sqq.; TILLEMONT,

Mémoires pour servir à l'histoire eccles., XV, 414 sqq.; ARENDT, Leo der Grosse u. seine Zeit

(Mainz, 1835); PERTHEL, Papst Leos I. Leben u. Lehren (Jena, 1843d); DE SAINTCHÉRON, Hist.

du Pontificat de Saint-Léon le Grand (Paris, 1845; 2nd ed., 1861-4); FR. AND P. BÖHRINGER, Die

Väter den Papsttums Leo I und Gregor I in Die Kirche Christi u. ihre Zeugen (Stuttgart, 1879);

BERTANI, Vita di Leone Magno (2 vols., Monza, 1880-2); GORE in Dict. Christ. Biog. (London,

1882), s. v.; LANGEN, Gesch. der röm. Kirche, II (Bonn, 1885), 1 sqq.; GRISAR, Gesch. Roms u. der

Päpste im Mittelalter, I, 308 sqq.; IDEM, Il Primato romano nel secolo quinto in Analecta Romana, I

(Rome, 1900), 307-52; IDEM, Rom u. die fränkische Kirche vornehmlich im VI. Jahrhundert in

Zeitschr. für kath. Theologie (1890), 447-93; GUNDLACH, Der Streit der Bistümer Arles u. Vienne

um den Primatus Galliarum in Neues Archiv (1899), 250 sqq.; (1890), 9 sqq., 233 sqq.; KUHN, Die

Christologie Leos I. des Grossen (Würtzburg, 1894); HEFELE, Konziliengesch., II (2nd ed.), passim.

J. P. Kirrsch

Transcribed by WGKofron

With thanks to St. Mary's Church, Akron, Ohio

The Catholic Encyclopedia, Volume IX

Nihil Obstat, October 1, 1910. Remy Lafort, Censor

Imprimatur. +John M. Farley, Archbishop of New York

The Catholic Encyclopedia: NewAdvent.org