Faith isn’t a lie , that’s a personal belief system. Religions might be a lie but you’d have to sauce your claim
We know Mohammed was a historical figure because he was rather recent as far as history goes . We know Christos was as well (7 Roman Emporers, Roman governors, 1 hebrew historian, 1 hebrew general and 2 Roman historians wrote about Christos, his followers and the problems caused by his execution— all within 70 years of said execution while contemporary or eye witnesses lived)
So these people existed. Belief in them as people is valid. Now. We’re they prophets or the son of God?
If that’s what you’re saying is a lie (since existence as humans is verified). You’d have to sauce your claim there.
Or what have you.