If Mohammed's claim is false, than all of Islam is false. This fear lies at the heart of other faiths. In First Corinthians, Chapter 15, Paul says, "But if there be no resurrection of the dead, then is Christ not risen: And if Christ be not risen, then is our preaching vain, and your faith is also vain." Such doubt is overcome only by faith and it is by faith alone that any and all religions exist.This is generally an informative article, with one caveat about the above paragraph. Paul's statement was not made out of fear or doubt. Rather it is a logical assertion that grounds the Christian faith, not in a religious conviction, or concoction of some idea, or some myth, but in an objective event in space/time history.
Cordially,
The Crucifixion/Resurrection is for Christians who the Passover/Exodus is to Jews. Interestingly enough, the historicity of the latter is more uncertain than the former.