The two brothers, Cryil and Methodius, belonged to a senatorial family of Thessalonica, but their mother was probably a Slav, Cyril went to Constantinople, where he was ordained priest. He taught philosophy in the university and defended the Gospel of Christ. The older brother, Methodius, after being governor of one of the Slav colonies, became the abbot of a monastery in Greece.
The two brothers were sent to the court of Ratislav at Velehrad. They needed bishops to ordain more priests. They journeyed to Rome bringing with them the relics of Pope St. Clement. Pope Adrian II consecrated them bishops and approved the use of the Liturgy in the Slavonic tongue.
Cyril died in Rome. Methodius continued the apostolate with success in Moravia, Bohemia, Poland and the neighboring countries. He died in Moravia, April 6, 885. Sts. Cyril and Methodius are honored as the apostles of the Slavs.
"Merciful God, You have enlightened the Slavonic nations by the teaching of the brothers Cyril and Methodius. Help us to assimilate the teaching of Your doctine and perfect us as a people united in the true Faith and its expension."