Think of it like a movie. The Torah is the first one, and the New Testament is the sequel. Then the Qu'ran comes out and it retcons like the last one never happened. There's still Jesus, but he's not the main character anymore, and the Messiah hasn't shown up yet.
Jews like the first movie, but ignore the sequels. Christians think you need to watch the first two but the third movie doesn't count. Muslims think the third one was the best, and the Mormons liked the second one so much that they started writing fan faction that doesn't fit with ANY of the series canon.
That's great! I had a similar comparison years ago on my blog, using Superman: The Movie (Old Testament), Superman II (New Testament), Superman II: The Richard Donner Cut (Catholic/Protestant Divide), Superman III (Islam), Superman IV: The Quest for Peace (Jehovah's Witnesses), Superman Returns (Book of Mormon).
I had some pretty good reasoning here, with II focusing more on MOM (Mary), III going off in a weird direction, and being ignored by fans of I and II, and of course IV leaving almost everybody cold. Returns used elements of the first two, Donner Cut being the same but different from II. I guess Man of Steel would have to be a doomsday cult or something, it wasn't out yet! Bottom line: all fiction.