Bogomil

Bogomil was a Bulgarian priest of the 10th century who founded the dualist movement named after him during the reign of Tsar Peter I. He is known chiefly from the treatise of Cosmas the Priest, who attacked his teaching that the visible world was the work of the devil and that the church's rites and hierarchy were worthless. His followers, the Bogomils, spread across the Balkans and Byzantium.