You don't "have" a god. You can't have them in your wallet; this example is moot.

Saying "There exists vkhmcdtr" would be a closer example. Now prove me that vkhmcdtr does not exist.

And even there, if you are some flavor of Christian, saying God can be reduced to an object, or an incarnate being, can be akin to blasphemy, because they are not a "Being." They are its antecedent. Which is one of the roots of metaphysics and of course Christian theology.

That's a specific, testable claim. If you claim Buddah or Jesus is in your bedroom that's a testable claim we can prove wrong.

Saying there's a magic invisible sky god is not a testable claim.