I'm willing to take on faith something which is a widely known theorem in logic, the proof of which I know is understandable and has been widely examined.
However something like the classification of finite simple groups which I know is big, complex, and has not been reviewed? Well when the authors publically say that they don't believe their own proof, I'm not inclined to believe it either.
Incidentally Asimov was being seriously unfair to religion. Yes, there are religious groups which act like he described. There are also groups of religious people who definitely don't. Religion itself doesn't act in any consistent way.
Cheers,
Ben