The Greek missionaries Saints Cyril (827-869) and Methodius (825-885) were the apostles of the Slavic peoples. Preaching Christianity in the native language, they brought the Slavic countries firmly into the sphere of the Christian Church.

Methodius was 2 years old when his brother, Cyril, was born in Thessalonica in northeastern Greece in 827. Cyril was given the name Constantine at his baptism. Methodius entered the service of the Byzantine emperor and worked faithfully, if without distinction, for a number of years. Constantine studied at the imperial university in Constantinople but refused the offer of a governor's post and asked instead to be ordained a priest. He was more intellectually inclined than Methodius and spent some years as the official librarian of the most important church in eastern Europe, Hagia Sophia in Constantinople. He taught philosophy for a time at the imperial university and was sent by Patriarch Ignatius on one...