The ideas of what constituted witchcraft, what made someone a witch, evolved over many centuries. Magic and magical operators were ubiquitous in the Graeco-Roman world, but when Christianity became the state religion, Christian theology introduced people to a particular view of Satan, and his evolving role in the eternal scheme of things made a major difference to the way magic was viewed, particularly by the authorities. The Church had to explain why Christian miracles were genuine but pagan magicians were frauds. Crucial to the argument were Satan and the daemons (the spiritual intermediaries of the Graeco-Roman world), and the eventual formulation of Christian teaching about them became the key element in later explanations of how witches were able to operate and why God allowed them to do so. Christ, the Apostles and the saints had supernatural powers so the Church could not ignore or abolish magic; it had to be reinterpreted in the light of developing theology. Daemons developed into evil spirits and became associated with the practice of all magic; thus it became difficult, if not impossible, for Christian theology to dissociate the practice of magic from traffic with evil spirits. The notion of a pact between humans and evil spirits became deep-seated and widespread; thus any act of magic was liable to be interpreted as the effect of a diabolical alliance.

The habit grew of blaming demons for any and all misfortunes. God was omnipotent but allowed Satan and his demons to punish people's sins or test their faith. There was a continual war between angels and demons, good and evil, and any human practicing magic was liable to be getting Satan's help, therefore they were on the side of evil and an enemy of God. Plagues, famines, natural disasters and all manners of personal misfortunes were attributed to demons and their human assistants. There was no single description of what witchcraft was, the term encompassed a…