In a letter to today's New York Times book review section, mathematician John Allen Paulos defends himself against the charge that his latest book attacks religion despite being "innocent of theology". His defense, interestingly enough, is not to deny that he doesn't know much about theology; on the contrary, he admits his own ignorance, but then claims that you don't need to know much about theology in order to be able to make sweeping statements about religion.
To justify this point, he goes on to say,
But how much theology is required to observe, for example, that assertions of God's existence suggest the obvious question, Who made God? If he's simply there and needs no explanation, then why not just say that about the world itself rather than multiply mysteries?I used to say the same thing back when I was about 20 or so.
But then, what I later came to realize is that a unitary, all-encompassing, boundless, infinite God is not of the same order of reality as a bounded, limited, contingent universe. God is, if he/she exists, by definition that which nothing is greater than, and than which nothing greater can even be conceived; therefore it makes perfect sense, as part of the very definition of "God", that God is uncreated, because there could not be anything greater than God that would create him/her. I have no trouble, on the other hand, conceiving of the possibility of something that is greater than the world. The world doesn't seem so infinite or perfect. I can imagine something greater than the world. The question of who created God, the Ultimate Reality and the Ground of Being, doesn't even make sense, given the definition we are working with; but the question of why there is something rather than nothing at all, on the other hand, is a difficult one, at least for me, to make sense of, unless I accept that there is ultimately some uncreated and infinite reality that lies behind the something that we observe. This is one reason why I came to believe in God, and this is one reason why I eventually rejected the argument that Paulos expressed in the above quote, and which I had embraced when I was twenty.
One key point about my own take on the Cosmological Argument is that, as an adherent of process theology, I do not see God as an omnipotent being who simply forced the world into existence via a single, all-powerful creative act. But the important point is not whether we are talking about a traditionally theistic God versus a panentheistic God; instead, what I think matters is that, from my point of view, there is an infinite, uncreated Reality, which serves as the wellspring from which the world evolved. The "how" of that dependence depends on one's specific theology.
None of this, of course, serves as a proof that God exists. Maybe the world does just exist for no reason whatsoever. Maybe we just are--period. But this gets back to my earlier point about science being about "what" and religion being about "why". One possible answer to the question of why there is something instead of nothing is simply to say that there is no reason--the world exists just because. That would be the atheistic response. Religion, on the other hand, is for me a way of saying that there really is a reason why we exist. And for me, that reason, is God.