religious/spiritual growth and evolution

Most deists saw the religions of their day as corruptions of an original, pure religion that was simple and rational. They felt that this original pure religion had become corrupted by “priests” who had manipulated it for personal gain and for the class interests of the priesthood in general.

According to this world view, over time “priests” had succeeded in encrusting the original simple, rational religion with all kinds of superstitions and “mysteries” – irrational theological doctrines. Laymen were told by the priests that only the priests really knew what was necessary for salvation and that laymen must accept the “mysteries” on faith and on the priests’ authority. This kept the laity baffled by the nonsensical “mysteries”, confused, and dependent on the priests for information about the requirements for salvation. The priests consequently enjoyed a position of considerable power over the laity, which they strove to maintain and increase. Deists referred to this kind of manipulation of religious doctrine as “priestcraft”, a highly derogatory term.

Deists saw their mission as the stripping away of “priestcraft” and “mysteries” from religion, thereby restoring religion to its original, true condition – simple and rational. In many cases, they considered true, original Christianity to be the same as this original natural religion. As Matthew Tindal put it:

It can’t be imputed to any defect in the light of nature that the pagan world ran into idolatry, but to their being entirely governed by priests, who pretended communication with their gods, and to have thence their revelations, which they imposed on the credulous as divine oracles. Whereas the business of the Christian dispensation was to destroy all those traditional revelations, and restore, free from all idolatry, the true primitive and natural religion implanted in mankind from the creation.

—Matthew Tindal, Christianity as Old as the Creation (XIV)

One implication of this deist creation myth was that primitive societies, or societies that existed in the distant past, should have religious beliefs that are less encrusted with superstitions and closer to those ofnatural theology. This became a point of attack for thinkers such as David Hume as they studied the “natural history of religion”.