The conceptual grouping and hierarchization of evil spirits appear only in the late Judaic period as a result of Persian and Hellenistic influences. In the New Testament the notion of the dominion of the Devil, the leader of all evil supernatural powers, crystallized into that of the antipodes of the heavenly kingdom. In Rome certain forms of magic had been penalized quite early. However, an edict dating to the reign of Constantine s the Great made a clear distinction between good and evil magic; this legal distinction was later abolished by the Byzantine Emperor Leo the Wise (886-913) in order to prevent tragic situations The Church, on the contrary, generally disapproved of magic and prophecy, considering them as idolatry, without any further Distinction or specific definition of the relevant acts. The communication between magicians and demons became a commonplace in Byzantine religion in accordance with the connection of magic with the Devil under canon law Contracts with the Devil, usually confirmed by a written agreement, often appear in popular texts, a corollary of the folk notion that evil spirits can transmit secret knowledge to people. The corruption of faith, the personification of evil, the instigation of every criminal act, the implanting of evil in the body of a “demoniac”, as psychopaths were then characterized, were included among the activities of the Devil, who used magicians as his instruments. In the official ecclesiastical texts he is assigned “homicidal” qualities. The theological approach to the entire issue depended on the particular period. Thus, the tendency for the popularization of the concept of the ‘Devil’ strongly prevailed in the Patriarchal texts of the late Byzantine period, when the Devil was more directly related to magic.