Isabel Rivers (Volume 2 of Reason, Grace, and Sentiment ) has a superb summary of the freethinkers’ account of the corruption of religion. In its origins, religion was “plain, easy, true” and was rooted in and expressed “nature.” But this was diverted “by priests, who, motivated by greed and playing on men’s fears of the unknown, have invented fables, mysteries, rites, ceremonies, and sacrifices and have made themselves indispensable to the performance of religious duties, thus converting religion int superstition and perpetuating their own trade, priestcraft . . . .

“In order for this advantageous state of affairs to continue they have kept the people in ignorance and made them slaves to tradition, custom, and prejudice. The religion of the priests is thus a cheat. The philosophers, who have remained in possession of the true religion of nature, have kept this knowledge secret through fear of the power of the priests and the hostility of the mob, and have publicly acquiesced in the ruling superstition. This process had its origin in pagan antiquity, when the split between priests and philosophers and between the superstitious traditional religion and the secret philosophy developed. True, primitive Christianity represented the attempt by Jesus to reconcile religion and philosophy and make the religion of nature plain to all men once more; however, institutionalized Christianity acquired the same fables, mysteries, and ceremonies as paganism and has become dominated by the priesthood in the same way and for the same ends. The freethinkers, like the classical philosophers, have preserved the religion of nature in secret and, while they are hampered by the restrictions of tradition and prejudice and the power of the priests, are covertly attempting to break these down and make the religion of nature plain once more so that the distinction between religion and philosopher will become meaningless.”

Or, more playfully, John Toland summed up this history in a rhyme from Letters to Serena : “Natural religion was easy first and plain,/ Tales made it Mystery, offrings made it Gain; /Sacrifices and Shows were at length prepar’d, /The priests ate Roast-meat, and the People star’d.”

Again, “As much as we revere those worthy men/ Who teach what’s peaceful, necessary, plain;/ So much we shou’d such Hypocrits impeach,/ As only Jargon, Strif, and Impire preach./ RELIGION’s safe, with PRIESTCRAFT is the War,/ All Friends to Priestcraft, Foes of Mankind are.”

Among other things, this line of critique is interesting for its evident echoes of Protestant polemics against Catholicism. For the freethinkers, as for Milton, “new Presbyter is but old priest writ large.”