The Argument goes something like this: "I refuse to prove that I exist" says God, "For proof denies faith and without faith I am nothing."
"BUT," says Man, "The Babel Fish is a dead giveaway isn't it? It proves you exist, so therefore you don't. QED."
"Oh dear," says God, "I hadn't thought of that." And promptly vanishes in a puff of logic.
"Ooh, that was easy." says Man and for an encore goes on to prove that black is white and gets killed on the next zebra crossing.