Saint Equal-to-the-Apostles Cyril (before accepting the schema, he bore the name Constantine) and his older brother Methodius were born in Macedonia, in the city of Thessalonica. Saint Cyril received an excellent education, from the age of 14 he was brought up with the emperor's son.
The young man early took the rank of presbyter. Upon his return to Constantinople, he was the librarian of the cathedral church and a teacher of philosophy. Saint Cyril successfully argued with heretics, iconoclasts and Mohammedans. Seeking solitude, he retired to Mount Olympus to his elder brother Methodius, but his solitude did not last long.
In 857, both brothers were sent by Emperor Michael on a missionary journey to preach Christianity among the Khazars. On the way, they stopped in Cherson and found there the relics of the Hieromartyr Clement, Pope of Rome. Arriving at the Khazars, the holy brothers talked with them about the Christian faith.