The
idea of the witch's familiar originated around the time
of the WEnglish renaissance, and was based on comments about witches in Leviticus:
"regard not them that have familiar spirits." The familiar was
thought to be a demon or imp who most often appeared in the form of a small
animal: cats, rabbits, toads and mice were all commonly assumed forms of the
witch's companion spirit, who was believed to trade favors to witches in return
for milk from the witch's breast (or, from a "third teat" or extra nipple- the
presence of this deformity figured in Henry the Eighth's complaint against Ann
Boleyn). (sometimes the devil appeared in its true demonic form, or as a human-animal
hybrid)
In
some cases, the familiar was the witch him/herself, who changed shape to
travel to Sabbat; later, they merely traveled upon the animals- goats, giant
cats, even pigs and dogs.
As
this belief became widespread, it was a common factor in witchcraft accusations.
The popular image of the old crone with her cat originates from a sad reality:
eccentric old ladies who kept animal companions were numerous among the women
tried for witchcraft, and many cats were likewise burnt as witches.