Gelasius (1) I., bp. of Rome after Felix III. (or II.) from Mar 492 to Nov. 496, during about 4½ years. At the time of his accession the schism between the Western and Eastern churches, which had begun under his predecessor, had lasted more than 7 years. Its occasion had been the excommunication, by pope Felix, of Acacius, patriarch of Constantinople, for supporting and communicating with Peter Mongus, the once Monophysite patriarch of Alexandria, who had, however, satisfied Acacius by subscribing the Henoticon, and afterwards the Nicene creed. There had been other grounds of complaint against Acacius, notably his disregard of the authority of the Roman see; but the above had been the original cause of quarrel. [See FELIX III.; ACACIUS (7).]

Acacias being now dead, the dispute concerned only the retention of his name in the diptychs of the Eastern church. Felix had 'demanded its erasure as a condition of intercommunion with his successors, but they had refused to comply. The patriarch of Constantinople was now Euphemius; the emperor Anastasius. On his accession Gelasius wrote a respectful letter to the emperor, who did not reply. To Euphemius the new pope did not write, as was usual, to inform him of his accession. Euphemius, however, wrote twice to Gelasius, expressing a strong desire for reconciliation between the churches, and a hope that Gelasius would, through condescension and a spirit of charity, be able to restore concord. He insisted that Acacias himself had been no heretic, and that before he communicated with Peter Mongus the latter had been purged of heresy. He asked by what synodical authority Acacias had been condemned; and alleged that the people of Constantinople would never allow his name to be erased; but suggested that the pope might send an embassy to Constantinople to treat on the subject. Gelasius, in his reply, couched in a tone of imperious humility, utterly refuses any compromise. He speaks of the custom of the bishops of the apostolic see notifying their elevation to inferior bishops as a condescension rather than an obligation, and one certainly not due to such as chose to cast in their lot with heretics. He treats with contempt the plea of the determined attitude of the people of Constantinople. The shepherd ought, he says, to lead the flock, not the flock control the shepherd. The letter thus asserts in no measured terms the supremacy of the see of Rome, and the necessity of submitting to it. "We shall come," he concludes, "brother Euphemius, without doubt to that tremendous tribunal of Christ, with those standing round by whom the faith has been defended. There it will be proved whether the glorious confession of St. Peter has left anything short for the salvation of those given to him to rule, or whether there has been rebellious and pernicious obstinacy in those who were unwilling to obey him."

In 493 Gelasius wrote a long letter to the Eastern bishops. Its main drift was to justify the excommunication of Acacias by asserting that he had exceeded his powers in absolving Peter Mongus without the authority of the Roman see, and plainly asserts the supremacy of the apostolic see over the whole church as due to the original commission of Christ to St. Peter, and as having always existed prior to, and independent of, all synods and canons. He speaks of "the apostolical judgment, which the voice of Christ, the tradition of the elders, and the authority of canons had supported, that it should itself always determine questions throughout the church." As to the possibility of Acacius being absolved now, having died excommunicate, he says that Christ Himself, Who raised the dead, is never said to have absolved those who died in error, and that even to St. Peter it was on earth only that the power of binding and loosing had been given. Such a tone was not calculated to conciliate. The name of Gelasius himself was therefore removed from the diptychs of the Constantinopolitan church. Gelasius wrote a long letter to the emperor in a similar vein, and exhorted him to use his temporal power to control his people in spiritual as well as mundane matters. This letter is noteworthy as containing a distinct expression of the view taken by Gelasius of the relations between the ecclesiastical and civil jurisdictions. Each he regards as separate and supreme in its own sphere. As in secular things priests are bound to obey princes, so in spiritual things all the faithful, including princes, ought to submit their hearts to priests; and, if to priests generally, much more to the prelate of that see which even supreme Divinity has willed should be over all priests, and to which the subsequent piety of the general church has perpetually accorded such pre-eminence. Gelasius also wrote on the same subjects to the bishops of various provinces, including those of East Illyricum and Dardania. In his address to the last he enlarges on its being the function of the Roman see, not only to carry out the decisions of synods, but even to give to such decisions their whole authority. Nay, the purpose of synods is spoken of as being simply to express the assent of the church at large to what the pope had already decreed and what was therefore already binding. This, he says, had been the case in the instance of the council of Chalcedon. Further, instances are alleged of popes having on their own mere authority reversed the decisions of synods, absolved those whom synods had condemned, and condemned those whom synods had absolved. The cases of Athanasius and Chrysostom are cited as examples. Lastly, any claim of Constantinople (contemptuously spoken of as in the diocese of Heraclea) to be exempt from the judgment of "the first see" is put aside as absurd, since "the power of a secular kingdom is one thing, the distribution of ecclesiastical dignities another."

In 495 Gelasius convened a synod of 46 bishops at Rome to absolve and restore to his see Misenus of Cumae, one of the bishops sent by pope Felix to Constantinople in the affair of Acacius, who had been then won over, and in consequence excommunicated. Before receiving absolution this prelate was required to declare that he "condemned, anathematized, abhorred, and for ever execrated Dioscorus, Aelurus, Peter Mongus, Peter Fullo, Acacius, and all their successors, accomplices, abettors, and all who communicated with them." Gelasius died in Nov. 496.

A curious treatise of his called Tomus de Anathematis Vinculo refers to those canons of the council of Chalcedon, giving independent authority to the see of Constantinople, of which pope Leo had disapproved, setting forth that the fact of this council having done something wrongly did not impair the validity of what it had rightly done, and that the approval of the see of Rome was the sole test of what was right. The tract contains further arguments as to Rome alone having been competent to reconcile Peter Mongus or to absolve Acacius, and in reference to the idea of the emperor having had power in the latter case without the leave of Rome, the same distinction between the spheres of the ecclesiastical and civil jurisdictions is drawn as in the letter to the emperor. Melchizedek is referred to as having in old times been both priest and king; the devil, it is said, in imitation of him, had induced the emperors to assume the supreme pontificate; but since Christianity had revealed the truth to the world, the union of the two powers had ceased to be lawful. Christ, in consideration of human frailty, had now for ever separated them, leaving the emperors dependent on the pontiffs for their everlasting salvation, the pontiffs on the emperors for the administration of all temporal affairs. Milman ( Lat. Christ. ) remarks on the contrast between the interpretation of the type of Melchizedek and that given in the 13th cent. by pope Innocent IV., who takes Melchizedek as prefiguring the union in the pope of the sacerdotal and royal powers.

Two other works are attributed to Gelasius in which views are expressed not easily reconciled with those of his successors. One is a tract, the authenticity of which has not been questioned, against the Manicheans at Rome, in which the practice, adopted by that sect, of communion in one kind is strongly condemned. His words are, "We find that some, taking only the portion of the sacred body, abstain from the cup of the sacred blood. Let these (since I know not by what superstition they are actuated) either receive the entire sacraments or be debarred from them altogether; because a division of one and the same mystery cannot take place without great sacrilege." Baronius evades the obviously general application of these words by saying that they refer only to the Manicheans.

The treatise de Duabus Naturis, arguing against the Eutychian position that the union of the human and divine natures in Christ implies the absorption of the human into the divine, adduces the Eucharist as the image, similitude, and representation of the same mystery, the point being that as, after consecration, the natural substance of the bread and wine remains unchanged, so the human nature of Christ remained unchanged notwithstanding its union with divinity. His words are "The sacraments of the body and blood of Christ which we take are a divine thing, inasmuch as through them we are made partakers of the divine nature; and yet the substance or nature of bread and wine ceases not to be." This language being inconsistent with the doctrine of transubstantiation, Baronius first disputes the authorship of the treatise, and secondly, seeks to explain the words away. But if the authoritatively enunciated views of Gelasius on the relations between civil and ecclesiastical authority, on communion in one kind and on transubstantiation, are inconsistent with those subsequently endorsed by Rome, yet, on the other hand, few, if any, of his successors have gone beyond him in their claims of supreme and universal authority belonging by divine institution to the Roman see.

Among his works is a treatise Decretum de Libsis Recipiendis, fixing the canonical books of Scripture, and distinguishing between ancient ecclesiastical writers to be received or rejected. It bears signs of a later date, having been first assigned to Gelasius by Hincmar of Rheims in the 7th cent. The most memorable of the works attributed to him is the Gelasian Sacramentary, which was that in use till Gregory the Great revised and abbreviated it. A new ed. was edited by H. A. Wilson (Oxf. 1894). See also C. H. Turner, in the Jl. of Theol. Studies (1900–1901), i. 556 ff. [SACRAMENTARY in D. C. A. ] A Sacramentary in several books found in the queen of Sweden's library, and published by Thomasius in 1680, is supposed to be the Gelasian one. The main authorities for his Life, besides the Liber Pontificalis, are the letters of himself and his contemporaries, and his other extant writings.

[J.B—Y.]