Let's clear things up.
Time is not linear, neither is the expansion of the universe. As the amount of mass in the universe decreases time slows down.
In the big bang theory, the universe was a point of infinitely small and infinitely dense material.The universe started to expand, and as it expanded, time sped up, creating a seeming explosion in the size of the universe, but in reality the expansion rate is relative to the speed of time and the size of the universe. By this logic, time is speeding up as the universe expands.
There is no god, the universe has always been, none of that 6 days bullshit. It was the big bang.