This quote comes to me straight from Tom Harpur, in The Pagan Christ. He describes the writing of the Bible as:
"The earliest Church fathers themselves admit that they took the high, symbolic, esoteric (or secret) wisdom that the Christian movement had inherited from Paganism- from Platonic philosophy and the Mystery Religions- and explained it, or rather downgraded it, by means of vulgar fables for the illiterate mob.... They were soon spreading these inner teachings abroad to the general public, and "in the process reducing the rich and sumptuous feast of wisdom to such a hash and porridge to the ignorant masses could find in some way digestible. Thus came Christianism which was the wreckage of Christianity."