Saints Cyril and Methodius
"Saints Cyril and Methodius, Equals of the Apostles, and Enlighteners of the Slavs came from an illustrious and pious family living in the Greek city of Thessalonica. St Methodius was the oldest of seven brothers, St Constantine [Cyril was his monastic name] was the youngest. At first St Methodius was in the military and was governor in one of the Slavic principalities dependent on the Byzantine Empire, probably Bulgaria, which made it possible for him to learn the Slavic language. After living there for about ten years, St Methodius later received monastic tonsure at one of the monasteries on Mount Olympus (Asia Minor).
St Constantine distinguished himself by his great aptitude, and he studied with the emperor Michael under the finest teachers in Constantinople, including St Photius, the future Patriarch of Constantinople (February 6).
St Constantine studied all the sciences of his time, and also knew several languages. He also studied the works of St Gregory the Theologian. Because of his keen mind and penetrating intellect, St Constantine was called "Philosopher" (wise). Upon the completion of his education, St Constantine was ordained to the holy priesthood and was appointed curator of the patriarchal library at the church of Hagia Sophia. He soon left the capital and went secretly to a monastery.
Discovered there, he returned to Constantinople, where he was appointed as instructor in philosophy. The young Constantine's wisdom and faith were so great that he won a debate with Ananias, the leader of the heretical iconclasts . After this victory Constantine was sent by the emperor to discuss the Holy Trinity with the Saracens, and again he gained the victory. When he returned, St Constantine went to his brother St Methodius on Olympus, spending his time in unceasing prayer and reading the works of the holy Fathers.
The emperor soon summoned both of the holy brothers from the monastery and sent them to preach the Gospel to the Khazars. Along the way they stayed in the city of Korsun, making preparations for their missionary activity. There the holy brothers miraculously discovered the relics of the hieromartyr Clement, Pope of Rome (November 25).