Many if not all arguments against Christianity or claiming God doesn’t exist are dependent on realities predicted by the Bible.
For example, the moral argument.
In the Bible God tells us there is evil in the world, and that the innocent will suffer from the effects of evil. God tells us that he is a God of wrath, and that wrongdoing will be punished in the way he determines.
Any and all reasoning of the opponents of Christianity is rationally defeated by what we learn in the Bible.