". . . We pray Thee, Lord, give to us, Thy servants, in all time of our life on earth, a mind forgetful of past ill-will, a pure conscience and sincere thoughts, and a heart to love our brethren; for the sake of Jesus Christ, Thy Son, our Lord and only Savior."

--From the Coptic Liturgy of Saint Cyril.

Cyril and Methodius were brothers, born into a senatorial family, who both rose to high positions in the world--Methodius became governor of a colony in the Slav province of Opsikion; Cyril, a leading philosopher at the University of Constantinople. Cyril, the younger of the two, was baptized Constantine and sent at an early age to study at the imperial university at Constantinople under Leo the Grammarian and Photius, was ordained deacon, and in time took over Photius's position at the university. Cyril also served as librarian at the church of Santa Sophia, where he earned the reputation and surname 'the Philosopher.' Methodius was also ordained. Both renounced the life of this world and went to live in a monastery on the Bosphorus.

In 861, Emperor Michael III sent Cyril deep into the Dnieper-Volga regions of Russia to convert the Khazars, who were Jews. His brother accompanied him. Both brothers were brilliant linguists and soon familiarized themselves with the Khazar language. They came back to their monastery after a successful mission, and Methodius became abbot of an important monastery in Greece.

Almost immediately (863) they were sent by the then Patriarch Photius of Constantinople to convert the Moravians at the request of Prince Rostislav. German missionaries had been unsuccessful in their attempts to convert the Moravians; Cyril and Methodius met with success because of their knowledge of the Slavonic tongue.

They invented an alphabet called glagolitic, which marked the beginning of Slavonic literature (the Cyrillic alphabet traditionally ascribed to Cyril was probably the work of his followers in Bulgaria, although both could have been inventions of Saint Cyril). Cyril, with the help of his brother, translated the liturgical books into Slavonic.

Meanwhile, they incurred the enmity of the German clergy because of their free use of Slavonic in Church services and because they were from Constantinople, which was suspect to many in the West because of the heresy rife in the East. Further, their missionary efforts were hampered by the refusal of the German bishop of Passau to ordain their candidates for the priesthood.

In Rome the pope had heard of their good work. Pope Nicholas I summoned them to meet him, but when they reached Rome he had died. The travelled at an unfortunate time; Photius had incurred excommunication (because he had been illegally appointed) and their liturgical use of Slavonic was strongly criticized. Nicholas's successor, Adrian II, received them warmly. They presented him with the alleged relics of Pope Clement, which Cyril was said to have miraculously recovered from the sea in Crimea on his was back from the Khazars.

Methodius was consecrated bishop and struggled on alone, often in dangerously hostile lands. He bore a letter from the Holy See commending him as a man of "exact understanding and orthodoxy." At the request of Prince Kosel of Moravia and Pannonia, Pope Adrian revived the ancient archdiocese of Sirmium (now Mitrovitsa), consisting of Moravia and Pannonia, independent of the German hierarchy, and made Methodius archbishop at Velehrad, Czechoslovakia (I don't know which two of the countries this is now part of).

Although he was supported by the pope, many German bishops resented his work among the Moravians (and probably the loss of territory). King Ludwig (Louis the German), urged on by the bishops, deposed Methodius at a synod at Ratisbon (Regensburg) and actually imprisoned him for two years in 870. Pope John VIII secured his release and returned him to his see, but thought it politic to forbid his use of Slavonic in the liturgy, although Methodius was authorized to use it in preaching. At the same time John reminded the German bishops that Pannonia and the disposition of sees throughout Illyricum belonged to the Holy See.

During the following years, Methodius continued his work of evangelization in Moravia, but he made an enemy of Rostislav's nephew, Svatopluk, who had driven his uncle out. Methodius accused Svatopluk of leading a wicked life. Accordingly, in 878, the archbishop was reported to the Holy See for continuing to hold Mass in Slavonic and for heresy, in that he omitted the words "and the Son (filioque)" from the creed, which at that time had not been introduced everywhere in the West, not even in Rome. Methodius was summoned again to Rome in 879. John was convinced that he was not heterodox, and impressed by Methodius's arguments, again permitted the use of Slavonic in the Mass and public prayers.