Martin was a confused double-minded occultist. On the Art Bell radio show, he is recorded as having doubts about criminalizing abortion and expresses admiration for the spiritual prowess of Native American Shamans.
Well, that is probably over-stating it but Martin's writing have led many to think his fiction is barely-disguised Gospel truth rather than, as you note, the product of a double-minded man who committed adultry with the wife of a friend.
I have been over this stuff with some of my solid Christian Catholics friends but it never penetrates. They love Martin and his fiction.