In the "Atheist Tapes", the theologian Denys Turner asks the troubling question "Why is there something rather than nothing"? Then the interviewer Miller rightfully answered with another question: "Why is there God instead of nothing"? Turner then claimed "God is not a kind of thing". I suppose what he meant by that is that God is somewhat indistinguishable from nothingness, he's a sort of abstract entity.
So the only reason - according to Turner - there can be something instead of nothing is if a not-a-thing entity, existing inside the state "nothing", suddently decides to create a universe.
Theology is really fun. We learn a lot about entities that are not "things".