“And God saw the light, that it was good: and God divided the light from the darkness.”
~ Genesis 1
There you have it, the perfect summation -- for what do the the remaining 66 books do? They tell the how and why (and through whom!) of this very thing: the dividing of light from darkness, and the goodness of that light. And in that brief statement, Moses also lets us know that God and God alone is the One who does it.
Mercy me, how I love a perfectly worded statement. Spare clarity has an elegance that gives words the clean power to transfer a living idea from one mind to another. The King James Bible is practically a textbook on elegant phrasing.
If you were asked to write a thesis statement for the Bible, could you have done it with a mere seventeen words?
(And isn't it astounding how every time you re-read the Bible, you will notice different things than you did in previous readings?)