Actually I don't know how anyone could answer this question concerning a faith in an invisible deity.
Well, I think that there is at least a possible answer, but it is one that many, particularly "Born Again" types, dislike.
The answer is to test the message against reason, logic and reality. It cannot tell you for sure if it is God, a Demiurge or just your own conscience, but it can test the message.
The next question is usually, "If the content is valid but the source unacceptable, should the content be accepted?" Personally I say "Screw the source."
Aslan is not a
Tame Lion