The universe exists. Everything that exists has a cause, so the universe needs a cause. The Big Bang was the beginning of the universe, and something must have triggered it. If you surmise that some aspect of the universe triggered the big bang, then something must have preceded that. At some point, we have to get to a point where there was nothing, and the only explanation for something to be created out of nothing is that God created it. If everything has a cause, the universe has a cause, and we cannot say that the universe was created by part of itself – that is illogical. The universe had to be created by something other than itself.
Now if the argument comes, well, if God created the universe, who created God? Well that is illogical; because that argument supposes that nothing can be the causeless cause, but here we propose that God is exactly that, a causeless cause, who does not need a creator. If you insist that God needs to have been created by something, let’s call it X, then we also have to ask, well, then, what created X? And then we can say that X was created by W – and so it goes, infinitely, and never does any being or entity have the ability to be a causeless cause because the argument is illogical.