Believing in God doesn't mean believing in a religion. Ever read any of Thomas Paine's works? He believed in a God but not the bible nor any revealed religion, but the sheer order and beauty he saw around him pointed to the existence of a creator. There are many people like that. If religion is so irrational explain why the likes of Einstein and Newton believed in a God? If they were irrational then how would they contributed so much to an area which has rationality as its basis. Isn't believing them to be irrational and then believing in the science they produced irrational?
Ironically I am certain most of your belief system that you take for granted has its basis upon revealed religion. What do you think the entire legal system and the constitution is based upon....religious law....most people's morality, its fundamental elements, is based on revealed religion. I know I can't convince you nor you can convince me. This isn't about that. But considering all those who believe in a creator as irrational is ridiculous.