God knows that if he were to show himself he would cease to exist. He himself has never claimed to exist. He allows himself to be sensed only so that the problem of his existence may be posed > Jean Baudrillard
Indeed, God functions primarily as an absence for believer and non-believer alike.
If humanity were to stumble across credible evidence for His existence, both would find themselves immediately out of business, and so too, to a large extent would God.