The fact is, God is unavoidable.
Even as the Universe evolves (see About genes, science, the Universe, evolution, God and
all that stuff), no one - no caliph, bishop, mystic, naturalist and,
let’s be clear, no scientist - is able to say for sure how the process started
or why, Chances are none ever will.
If
the Big Bang started it, next up is what started the Big Bang? If the Big Bang
started itself, how did it have the necessary explosives? If it wasn’t
an ‘explosion’ in that sense at all, just quantum fluctuation and instant
expansion*, where did the quanta come from and why do they fluctuate?
Any way you think about it, you're into an infinite regression. In one Creation story the world stands on the back of a giant turtle, famously requiring turtles all the way down. There’s no way out of infinity. Unless the mystery is not “out there” at all.
Our human brain did not evolve to deal with the infinite, which necessarily involves there being or not being a Beginning; it evolved to deal with our situation in our “environment” here on Earth. When the simplest single-celled life emerged in some hot spring somewhere unimaginably long ago, its concern was surviving in the hot spring, not on the planet Mars. Naturally, it's still at it.
To dig a little deeper
into this, we are able to grasp without a sense of fathomless mystery Earth’s very
long past and formation, and before that, a time when Earth wasn’t yet around.
And it doesn't stop there. Though
we can understand Earth isn't going to last forever, it’s not hard imagining
an infinite future for the Universe.
Perhaps there’s no mystery,
no evolution, no science, and no God; never were. What on earth would explain that?
Us.
*Most scientists seem to accept the Universe is expanding, but not on how fast.