Would you call math a religion?
my father (a graph theorist) did once, and i think he quoted someone like godel as saying "math is the only true religion."
apparently, all math follows logically from a few basic axioms, which are unprovable in nature. if one such axiom should ever be overturned, it takes down a relatively large portion (or all of) math with it. and every mathematician recognizes this: their conclusions are only as good as their assumptions. and so it takes a degree of "faith" to accept math.
but i suspect it's more of an "in-joke" among mathematicians than a serious point.