wiki Devil in Christianity
https://en.wikipedia.org/wiki/Devil_in_Christianity
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Particularly in the medieval period, Satan was often shown as having horns and a goat's hindquarters ... and with a tail. He was also depicted as carrying a pitchfork,[20] the implement used in Hell to torment the damned, ...
None of these images seem to be based on biblical materials, as Satan's physical appearance is never described in the Bible or any other religious text. Rather, this image is apparently based on pagan Horned Gods, ...