Spiritism
In my quest for the truth I investigated psychic phenomena, parapsychology, OBEs because I thought it a more scientific (and therefore reliable) approach to answering metaphysical questions than consulting the Bible. And so of course I was accussed of the heinous sin of spiritism; but when I asked my accussers to define just what they meant by 'spiritism' they could never give me a clear answer.
I looked up the word in the dictionary and found that it refers to mediumship, table-tapping, and similar chicanery. Well, that certainly didn't describe anything I was doing. Even back then, I knew that psychic mediums were con artists.
I tried to explain all this to the brothers, but their minds were closed. Reading books on the paranormal was spiritism (unless you bothered to consult a dictionary), which made me ipso facto a witch in league with Satan.
Some time after that I had my first OBE (which was totally fucking awesome, BTW) and was foolish enough to tell my mom about it. According to her, the demons were now trying to rip me out of my body so they could take possession of the vacated cadavre! I tried, in vain, to explain how silly that was and that it wasn't even consistent with her own theological beliefs; but to no avail.
Ah, religion...