I have read a LOT of sci-fi, including loads of Asimov. None of his characters are proven historical characters like Jesus. What most people find hard to believe is his claim to be God, his death, resurrection, ascension etc. I'm saying that I do believe those. Saying that all of that is fiction... I really find that hard to believe.

That said, although many would love a long discussion / argument about it here. For personal reasons I am not going to say more here today than I already have.