St.Clement belonged to the closest assistants of the Solun Brothers Constantine and Method. He was often called Clement Bulgarian, Ohrid, Macedonian or simply Slavic due to his origin or places where he was active. In the town of Chersoneses Constantine found the relics of one of the first popes - St. Clement. As an honor to him he received his name and had used it all his life. Into the present-day Macedonia, in the town of Ohrid Clement founded the monastery and built two or three churches. He was working hard on the mission work among that-time Slavs and he was teaching the domestic clergy. He became the first Slavic bishop in Bulgaria. There is no unified opinion about whether Clement may be considered to be the author of the new - simplified Slavic script - Cyrillic alphabet.
St. Gorazd's name had old Slavic origin. It referred to a man who was "talkative". He was one of the colleagues of the Solun brothers Constantine and Methodius after their arrival to the Great Moravia. He is considered by some to be the author of St. Method's biography written in the old Slavic language. Others think that when Pope John IX renewed the Great Moravian archiepiscopate in the year 900, he named Gorazd into this position. There are, however, no documents confirming these facts.