Repose of Saint Cyril, Equal-to-the-Apostles and Teacher of the Slavs

Constantine, later named Cyril, was born c. 827 in Thessalonica, the youngest of seven sons; his eldest brother was Methodius. Learned in languages and philosophy, he taught in Constantinople and was sent on missions to the Arabs and the Khazars. At Cherson in the Crimea the brothers found what they took to be the relics of Pope Clement of Rome.

In 863 Prince Rastislav of Moravia asked for teachers who could preach in the Slavic language. Constantine created a Slavic alphabet and with Methodius translated the Gospels and the services. In 867–868 the brothers brought Clement's relics to Rome, where the pope approved the Slavonic books. There Constantine fell ill, became a monk with the name Cyril, and died on 14 February 869. He was buried in the church of St Clement.