Shiva

Satan ,I think, is modelled on  Shiva, the Hindu deity.It was Satan's horns that put me on this track. The horns of Satan are the points of the crescent moon that adorns the head of Shiva. It was commonplace enough for a nascent religion to debase the older religion which it tried to supplant, for instance the Zoroastrians worship Ahura Mazda and the demons are the devas, in Hinduism the devas are the gods and the demons are the asuras. Yet another factor that convinced me was that Shiva is accompanied by a wild bunch, the devils and imps of Satan perhaps.And then there is Shiva's trident, a weapon patronised by Satan and others.
If anyone elaborates on my theory, which I dont think anyone else has suggested before, please acknowledge your debt to me as prime mover!