The pain from getting into witchcraft was residual. The pain of the religiosity of the Jehovah's Witnesses, that was causal

[Vladv1]

Contrary to popular belief, while I did read The Satanic Bible I never became an actual Satanist--the whole concept seemed kind of silly, to be perfectly candid--but I certainly did dabble in the dark arts, and I don't doubt for a second that it f**ked with my head to an almost immeasurable degree. I believed in the occult, and some people will say, "How can you believe in the occult and practice black magic and not be satanic?" Well, there's a line there. Talk to anyone who has been involved in the occult and they will tell you that there are a lot of different factions for different types of magic. And as with anything else, there are good and bad aspects to the occult. I only know that both witchcraft and the Jehovah's Witnesses caused me a good deal of pain for a great many years. They're different, of course. 2 The pain from getting into witchcraft was residual. The pain of the religiosity of the Jehovah's Witnesses, that was causal. It's like when people say, "Hey, you're on drugs, so your relationships are sh*tty," and you respond with, "No, my relationships are sh*tty, and that's why I'm on drugs." Either way, you're f**ked-up.

By Dave Mustaine "A heavy metal memoir"

"The pain from getting into witchcraft was residual. The pain of the religiosity of the Jehovah's Witnesses, that was causal".
Could you please reword the aforementioned, I get the separate words, but not the whole meaning. I have asked several native speakers but they can't get it either. Please help.

 

[Tarheel]

The word "causal" indicates that somebody caused it. Context should tell you what is intended as the cause.