Saying "God did it" is an easy dodge. Saying how it was done, that takes science.
Saying that the universe created itself out of nothing is even a bigger dodge. There is nothing in our knowledge of Science that say it is possible. In fact the Laws of Physics as we understand them says that it is impossible. That is why the secularit theorists come up with absurd things like "the Laws of Physics didn't exist when the universe was made", and other silly things.
True as I have also posted. And most scientists ignore the Bible - thankfully Galileo and Newton accepted that truth comes from both science and the Bible.
The most common model of Big Bang theory is that our universe began with a singularity with zero dimensions - but most scientists are at a loss to explain why this happened and so they create fanciful theories with no observational evidence - in other words: blind faith.
I have already posted on Isaiah 40:22,26 as it relates to the fine tuned expansion of our universe involving plural forms of God's energy (Hebrew ohnim) such as gravity and dark energy. But I have not addressed the illustration in verse 22 that hints at how the singularity was formed.
Isaiah 40:22
There is One who dwells above the circle
* of the earth,
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And its inhabitants are like grasshoppers.
He is stretching out the heavens like a fine gauze,
And he spreads them out like a tent to dwell in.
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Most simply scoff at the illustration of a tent - not realizing this illustration hints at both the shape of the universe (is the universe flat like a stretching out flat tentcloth?). But tents have more than one tent cloth.
The sacred "tent of meeting" (tabernacle) in geometric terms is/was a rectangular prism. The hint as to how the singularity was formed is in the fact that the corners of this tent are actually points with zero dimensions if one ignores the width of the tentcloth which is not specified in the Divine direction of its construction. Only two dimensions of these tentcloths are specified - another hint I think.
Personally, I favor a collision of branes model but based on membranes/cloths with only 2 dimensions. If two 2-d branes were to intersect on edge, the intersection point would be a singularity!
It's just my theory of course. But I do think God might have fine tuned a collision of two 2-d branes to release an immense amount of energy at a singularity.
Of course, that fine tuning involves all the laws and properties of our universe, not simply a big bang!
Another problem with popular scientific theories is the belief that time began at the origin of our universe - not all scientists agree with this btw - as in modern day models of the Oscillating theory - which are wrong btw.
Indeed, our universe specific space-time did begin at the origin of our universe.
However, cause and effect cannot proceed without time. I call the time in which cause and effect proceeded at the origin of our universe: 'primordial time.' Otherwise why is the Divine Name a verb in the Hebrew imperfect state = action in progress not yet complete? All verbs require action and all action requires time!
We do not know if primordial time always existed - that is another subject! But it may have since Jehovah is God's name, and Jehovah always existed. Or.... (for another post).