CYRIL (Constantine) and Methodius, Saints. - Greek brothers, called "apostles of the Slavs"; they lived in the 9th century.
I. AT BYZANTIUM
C. and M. were born in Thessalonica to the noble magistrate Leo. After the premature death of their father, the protection of the children was assumed by the imperial chancellor Theoctistus. M., a practical jurist, was entrusted with the administration of a province inhabited by Slavs, probably Macedonia.
The younger, Constantine (who took the name C. upon becoming a monk), was summoned by Theoctistus to Constantinople to be educated together with the underage emperor Michael III, among whose teachers Leo, called the Mathematician, and Photius, the future patriarch, stood out. Having finished his studies, C. refused a court career and received the sacred Orders, afterwards accepting the office of patriarchal librarian. But after a short time he withdrew secretly to a monastery. Found again, he was unwilling to return to the office of librarian; he nevertheless accepted the chair of philosophy, in which he distinguished himself so greatly as to receive the nickname of "the Philosopher." At that time he went to the court of the caliph of Baghdad as imperial ambassador.
Meanwhile the year 855 brought important political changes. Bardas, uncle of the emperor Michael and bitter enemy of Theoctistus, succeeded in winning completely the trust of the young emperor and had Theoctistus killed. The empress mother Theodora had to withdraw from the government and was later confined in a monastery. Under the government of Michael III the direction of state affairs passed effectively into the hands of Bardas. The tragic end of Theoctistus and Theodora, the protectors of C. and M., had grave consequences for them as well. M. renounced his office and became a monk in a monastery of Olympus in Bithynia. C. too withdrew from public life and soon joined his brother at Olympus, where both devoted themselves to prayer and study. The political changes also had their consequences in the ecclesiastical sphere. In 858 the patriarch Ignatius was deposed and Photius, friend and counsellor of Bardas, was elected.
C. and M. kept themselves out of this painful conflict. Around 860 the emperor entrusted C. with a politico-religious mission to the Khazars, then residing on the coasts of the Black Sea between the Don and the Caucasus. C. had to bow to the emperor's order and set out accompanied by M. During the stop at Cherson in the Crimea he took an interest in the tomb of St. Clement, pope and martyr. Having identified the traditional site of the tomb, C. discovered the relics of St. Clement and took them with him. C.'s mission achieved its intended purpose: numerous Khazars received Baptism and the Chan formed a friendship with the emperor. Having returned to Constantinople, C. settled near the church of the Holy Apostles and M. withdrew to the monastery of Polychronius, of which he became abbot.
II. MISSION IN MORAVIA
Meanwhile an embassy from Prince Rostislav (846-60), sovereign of Great Moravia, arrived in Constantinople to ask for a bishop and missionaries who spoke the language of his people. Moravia had already been partly Christianized through the work of Western missionaries, who, besides spreading the Christian faith, favored the expansion of the Germanic Empire. Rostislav wanted to free his State from the political influence of the German bishops and to procure for Moravia its own hierarchical organization. The emperor chose C. and M. for this mission, because they, being natives of Thessalonica (Salonika), spoke Old Slavonic well. Neither the Moravians nor the other Slavic peoples had at that time a literature of their own. Therefore, before departing, C. composed a new alphabet and began to translate the sacred books into Old Slavonic. In 863 C., accompanied by M. and by some disciples, set out for Moravia provided with a letter of recommendation from the emperor.
In Moravia C. and M. devoted themselves principally to preaching and to the formation of the young clergy. With the help of M., C. also translated Byzantine and some Latin liturgical texts into Old Slavonic. Preaching and the celebration of the sacred functions in the language understood by the people had great success, but at the same time it aroused the hostility of the German clergy, who accused C. and M. of heresy at Rome. After about three and a half years of missionary activity in Moravia, C. and M., with some chosen disciples, went to Rome. They were solemnly received by Pope Adrian II (867-72) because they carried with them the relics of St. Clement. The Pope, informed of their activity in Moravia, recognized the orthodoxy of C. and M. and approved the use of the Old Slavonic language in the liturgy. M. was ordained priest, C. probably bishop. Meanwhile C. fell gravely ill. During his illness he took the monastic habit. C. died on 14 February 869 and was buried in the basilica of St. Clement.
After negotiations with the princes of Moravia and Pannonia, the Pope appointed M. archbishop of Sirmium and sent him to Moravia as pontifical legate. While returning, M. was arrested and imprisoned, after a semblance of a trial held in a synod in which, among others, Adalwin of Salzburg, Anno of Freising and Ermenrich of Passau took part. Only after three years, thanks to the energetic intervention of the new pope John VIII (872-82), was M. released and returned to Moravia. But he was again accused of heresy at Rome, especially through the work of the German priest Wiching, who succeeded in winning the sympathies of Prince Svatopluk (870-94), Rostislav's successor. M. went again to Rome, where he fully cleared himself, while the Slavonic liturgy was again approved. Moravia received its own hierarchical organization with M. at its head; but Wiching too, thanks to the protection of Svatopluk, obtained the suffragan see of Nitra. M. devoted the rest of his life to consolidating the ecclesiastical organization, availing himself of an extensive literary activity. But his perfidious suffragan Wiching succeeded in completely alienating Svatopluk from M. and with various intrigues greatly embittered the last years of his archbishop. M. died on 6 April 885, after having designated as his successor his disciple, the Moravian nobleman Gorazd.
III. LITERARY ACTIVITY
St. Cyril is rightly considered the father of Slavic literature, the inventor of the Slavic alphabet and the first writer in the Old Slavic language. He translated into this language the Byzantine liturgy, that is, the Euchologion (Ritual), the Gospels, the Epistles, and also some Latin liturgical texts; after his death Methodius completed the translation of Holy Scripture, except for the books of Maccabees, translated the Nomocanon and an anthology of the works of the Holy Fathers. Cyril, on the other hand, wrote in Greek a brief history of the discovery of the relics of St. Clement, a panegyric and a hymn in his honor, and a polemical book against Jews and Muslims, later translated by Methodius into Old Slavic. The literary activity of Sts. Cyril and Methodius was continued by their disciples, especially in the Balkans, whence it later penetrated into Russia as well.
IV. THE CULT
Immediately after their death C. and M. were venerated as saints by the Slavic peoples, both in the Western and in the Eastern rite. Besides the respective days of their passing - C. 14 February, M. 6 April - their common feast is also celebrated. In the Latin rite, fixed at 5 July at the time of its extension to the universal Church (Leo XIII, 25 October 1880), it was later transferred to the 7th of the same month (11 December 1897); in the Eastern rite it is celebrated on 11 May by both Catholics and dissidents. The work of Sts. M. and C. left a clear imprint on the initial Christian culture of the Slavic peoples, and for this reason they are venerated by them as the "apostles of the Slavs." However, C. and M. were not numbered among the saints of the dissident Church of Constantinople, probably because of their constant fidelity to Rome.
Bibliography9 works
Giuseppe Olär

Latin version of the paleo-Slavic lives with notes); Fliche-Martin-Frutz, VI, pp. 467-80.