Throughout history man has made countless efforts to give explanation to their being.
Atheists do so by using logic. Claiming that the existence of a higher being is illogical.
Theists do so by using an illogical explanation. Stating that 'logic' is a creation of man. And existence is beyond our understanding.
Existence has no logical explanation. The beginning, and the end of existence are illogical. It simply IS.
In my honest opinion, the Big Bang theory is something that may be proven, no matter how many countless years in the future, while the existence of God is something that you'd have to bring someone back from the dead to prove... but then that would disprove God at the same time, as you cannot bring a soul back from Heaven or Hell by any practical means, I believe (Correct me if I'm wrong).
Now, GCK, I respect your religion, and I have no problem with you being a theist, and, from the looks of it, you are starting to tolerate the atheists around here (As in accepting our place here), and you're right, existence is something that cannot be explained, at least, not by science at the moment, but cannot be proven by science nor theism of any sort, as you would have to have contact with God or Allah or whoever else is your god, and I don't think there is anyone out there, probably the closest thing to it being the Pope, and I think that, according to Catholicism, God speaks through his actions, not through him directly.