Called a "familiar," from the medieval superstition that Sitan's favorite form was a black cat. Hence witches were said to have a cat as their familiar.
In ancient Rome the cat was a symbol of liberty. The goddess of Liberty was represented as holding a cup in one hand, a broken scepter in the other, and with a cat lying at her feet. No animal is so great an enemy to all constraint as a cat.
In Egypt the cat was sacred to Isis, or the moon. It was held in great veneration, and was worshiped with great ceremony as a symbol of the moon, not only because it is more active after sunset, but from the dilation and contraction of its pupil, symbolical of waxing and waning. The goddess Bast (Bubastis), representative of the life-giving solar heat, was portrayed as having the head of a cat, probably because that animal likes to bask in the sun. Diodorus tells us that whoever killed a cat, even by accident, was by the Egyptians punished by death, and according to Egyptian tradition, Diana assumed the form of a cat, and thus excited the fury of the giants.