Who's redefining "nothing"? Nothing, as in no definite, contingent, limited and thus intelligible thing. That's the point of the cosmological argument, that behind all the natural things we're familiar with, there must be a necessary, supernatural being. The balancing act is to distinguish that being, God, from nothing. The more we think we understand God, the more we naturalize him, turning him into a mere finite being who would himself require a deeper explanation. And the more we refrain from limiting God with our concepts, the more God seems like nothing at all.

Instead of "starting" with the assumption that theism is preposterous, I wrote literally thousands of pages exploring many, many aspects of theism and religion, including the proofs of God, the history, the theology, the sociology, the politics, and so on.

Save face all you like. Just know that the standards are higher when I'm around.