Oooo, this is fun. I think Mr. Smith was actually cybernetically engineered by space faring cyborgs. Since it was the 1800's, it would be impossible for anyone to understand what had happened to him. Think about it. He was anesthetized, but he interpreted that as Satan attacking him. Really, it was nanoprobes infiltrating his nervous system causing him paralysis and, as to be expected, anxiety. After that, he could hear "them" communicating to him, and sometimes he would get holographic messages sent to him. He then knew, that most people wouldn't understand this thing happening to him, so he related his experiences in a religious context. He was smart enough to know that he would be killed or ostracized if he attempted to explain things in a literal sense. So, as you see, it makes sense from a scientific perspective what really happened to him.
Bam. Too easy.
Impressive. I sense a hybrid scientology/Mormonism offshoot in the making.