Hmmm, interesting question.... I guess I would ask what page and line I am on in my current book and what my password is for my computer. Also I would ask him what I was thinking of 5 minutes ago. If he got those questions right, then I guess I'd ask him who I think of when I jack off. (Sorry if I offend, just being honest.)
Of course as previously mentioned the voice might be the devil so I would ask him to erase all "Evil" thoughts from my mind and forgive all my past and future sins. (Something the devil would never do.)
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