The fact that there are so many different deities out there that are worshipped by so many different believers doesn't make religion polytheistic, it simply makes the different versions mutually-exclusive. The human mind is as yet relatively unchartered territory. Within it, the laws of physics are void. Sure, I could. My ability to conceive of anything is limited only by my imagination mixed with the sum total of my accumulated knowledge and salted with the flavor of emotion.
Religious conceptions rely almost entirely on the imagination and emotion parts of that equation.
Its basic appeal is to emotion and not to intellect. Dissecting God using scientific tools therefore is pointless, because these two phenomena are blind to each other. Like you wouldn't use a camera to record the song of a blackbird. If belief in God remained a purely emotional phenomena, there wouldn't be much to quibble about. I believe it.