The only way that "believe first, see later" makes any sense to Me is if our beliefs have the power to create the objects of our belief.
In the world of the entrepreneur, this is how it tends to work: First you conceive of a product or service, and in that conceptualization you find the means to make it real.
In the world of religion, perhaps it works the same way: Imagine a god, and then the god becomes real to you -- Not because it existed previously in that form, but because you either thought it into being or reshaped a pinch of divine "stuff" to suit yourself.
If this is the mechanism at play, then it isn't surprising that gods tend to shape themselves around preexisting beliefs and tastes. This explains a lot of things -- Different gods, different religions, different divine "laws" -- that just don't fit with the idea of a single, eternal personal god. What worked in ancient Israel doesn't work today, and what works today probably won't work a few centuries from now.