From Satan Service
This term has mutated through the centuries of its employment. Its origins are shrouded in spells and controversy. That it was never religious prior to the 1950s after the repeal of the British Witchcraft Laws is the important aspect of its relationship to religious satanism, which enjoyed a similar legitimizing.
That 'witch' was an epithet of heretics targetted for hanging and burnng as during the European Witch Craze is well-known, but they were also a name for a monster who cursed crops, dried up lactating mammary glands, and brought sickness and death. The 'craft' of such beings was inevitably deemed sorcerous, malefic, and associated at points with the worship of, or service to, Satan.
Shedding their skin for revels by night at 'sabbats', and flying on psychedelic brooms, whereat the Infernal Consummation with the cold-pricked, goat-horned High Priest arranging for the visitation of Old Nick Himself upon the assembly.