Hmm - cause and effect.
I am sure we all agree that something / someone "caused" the universe.
This is a scientific fact agreed by everyone - I hope!!!
Now was that something God - I think it was was. I wish I could point to God himself as proof but I can't - so faith is involved.
The alternative explanation is that somehow - in the beginning, there was nothing and the nothing exploded and this produced "over time" the entire universe. The problem with this example is that it is scientifically impossible and flys in the face of everything we understand about the universe and all science. You put nothing in, you get nothing out.
So the next question is - Where did God come from? This is tricky to answer as we are discussing something that is simply beyond human understanding.
But - whatever caused the universe to explode into existance existed outside the universe as it did not exist yet. So we know that there is definately something outside of the physical universe.
My brain has not hurt this bad since the last episode of Lost!!!!!