Its basically like a form of psychotherapy, or even a cognitive program if you like.
Its designed to cultivate a kind of consciousness/perception which is free from anxiety and has faith that for what ever happens things will be fine.
So in this case I think Zen Buddhism is probably the purest(least BS) religion out there.
However because of that, it does not appeal to most people.
Rather Christianity with its myth-indoctrination into believing that Jesus is your "rock" and he will protect you (if you do x), gives people a much easier means of reaching that state then just sitting and counting your breath. However the problem there is the strict and at times unnecessary morality.
Just to clarify, I am referring to the more esoteric side of religion, not so much the politically corrupt exoteric side. (Yet this still applies to both in some degree)