An aside on the multiple author theory: CMK, I find it helpful to think of it as a sort of modern midrash, a commentary on the text. I recommend Richard Friedman’s book, WHO WROTE THE BIBLE, which reads like a detective story in tracing the history of Israel and assigning different authors to different time periods. It’s intriguing: I’m not saying one needs to believe it, just like one needn’t to believe every midrash, I’m saying it’s an interesting and intricately woven intrepretation.
However, even if there were multiple authors, there was certainly a single Editor (called Redactor), and we are compelled to look at the work as a single work of a single Editor/Redactor (whether that was a human scribe or God the Author.)
OK, back to the main topic: The text was written for the audience of its time, regardless of who you think is the writer. It expresses concepts in terms that the contemporary reader could understand, so it speaks of the “four corners of the earth” and of the sun going around the earth, and of the moon as a “lesser light” rather than as “reflected light.”
I repeat my contention, that this is a poetical description that still is applicable. OK, so God starts the Big Bang with the command, “Let there be light!” rather than by uttering Maxwell’s equations. If the text had started out with the equations for matter-energy conversion, it would have been lost long ago, because no one would have read it but physicists and astronomers.
OK, so the text describes primordal chaos in terms of darkness and unleashed water; that was a very apt poetical description 3,500 years ago, and is still a very apt poetical description today. Far better than describing chaos in terms of electron attraction and nuclear fission, at least if the text is going to be generally available.
OK, the text describes the creation of man from dust, rather than from primordal sludge. Reasonable enough as poetic license, I think. Far easier to grasp the main concept – the humbleness of mankind’s beginning – than describing the creation of man through evolutionary mutation of chromosomal matter. “Dust thou are and to dust thou shalt return,” has a lot more poetical oomph to it than, “Basic DNA strands thou are and to component atoms shalt thou return.”
Notice what the text DOESN’T do that so many other creation-mythos did. The text DOESN’T talk about life springing from the body of a slain god or hero. It DOESN’T describe the stars as the outlines of dead heroes or monsters. It DOESN’T describe the sun as a big chariot of fire, but as a “light to rule the day.” In short, the poetry is still meaningful, despite our much deeper understanding of how the universe works. Most of us may not be able to take the text as a literal, word-for-word scientific description; but we can take the concepts and imagery as still valid.
That, to me, is as much proof of divine authorship (or editorship) as anyone could ask for.