Everything you can observe existed compressed into a single hyper-dense particle. It existed that way for all time, until one instant, nothing happened, and that non-event caused the particle to violently explode unleashing everything you can measure, plus time and space. Everything - all matter and space and time came from nothing, by itself, with no outside motivating force.
But your ridiculous belief in a magical man in the sky who created everything from nothing - that is an insane belief.
< off sarc >
I trust that you are being sarcastic /s. There is nothing more irrational than the belief that the universe, with all of its unimaginable complexity, is the result of nothing more than time + chance.