It simply suggests that the criteria that God uses, when deciding when to make His presence known, are not limited to the professed religion of the person in question.
That sounds like you're agreeing with me. If God gives people mystical experiences no matter what their religion, mystical experiences are no good in showing that the religion is true. Of course this is a matter of degree. The wider the range of people get the experiences, the worse the experiences are at showing anything.
If beings other than God (such as the Devil) can give out mystical experiences, it's even worse. Mystical experiences not only don't show that the religion is true, they don't even show that "God exists" is true. At this point I don't see why you care that it's not just a brain malfunction, because even if it wasn't, you have no way to tell between an experience sent by God, one sent by the Devil, and there being a sorcerer on every block who occasionally pulls pranks by giving random people mystical experiences.
(As for why the Devil would want to do that? Maybe he knows that people interpret mystical experiences as evidence for their religion being true and he can incite religious conflict by giving people of opposing religions mystical experiences.)
That sounds like you're agreeing with me. If God gives people mystical experiences no matter what their religion, mystical experiences are no good in showing that the religion is true. Of course this is a matter of degree. The wider the range of people get the experiences, the worse the experiences are at showing anything.
It does not prevent said experiences from showing the existence of God, or from hinting at the criteria He finds important.
...If beings other than God (such as the Devil) can give out mystical experiences, it's even worse. Mystical expe
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