Laws of physics as they exist in our universe. When one goes backwards to the singularity, all the laws of physics break down. Time, gravity, laws of thermodynamics, periodic table of elements, etc all came into existence after the Big Bang.
Therefore, events before the Big Bang cannot be defined, because there's no way one can measure within our universe what happened prior to the big bang.
That's quite a religion you have there.
No, it would be a religion if I believed it. I only accept what physicists theorize about it with full awareness that they are only theorizing.
The big bang theory is just that - a theory. It may even be mostly correct. The fact, though, that there are properties of the theory that don't meet observations doesn't necessarily mean that the physics are wrong. It may mean that the theory is incomplete.