I ask this because it seems to me there is a striking paradox to a God's existence claim. I do think that what is and what isn't are conceptions that depend on our perception of the universe. So how, then, if we take down this road of thought, can we speak of existence outside the physical realm? Is it only possible to do so if we relate some physical effects to the existence of the deity in question? Is this why religions need to make claims about the physical world - because else, they're devoid of meaning?