and why you are able to believe in the existence of gravity and not the one of God ?
If you ask who created God, you've already broken a mathematical law.
There are 2 different groups : Creatures, and Creator. If someone created God, then he's no more a creator.
Define groups you work on then ask real questions.
IMHO I find God easier and more logic to believe in, than believing in Probability or Gravity outside their scientific place.
BTW, God can't be like human or other things, you still can't know how much dimensions the world has.
If dimensions are more than the 3D+T (Maybe 11?) Then God has at least the same dimensions.
(if time is a dimension, then God is 4D and he can modify the time, without having time take an effect on God)
People believing in 3D gods or human-like gods need now to change their minds...