What does Genesis 1, and the other early genesian data do? As per my previous post, it tells us what happened, it is there to give us knowledge, but what is the function of this knowledge?
I think one major function of the knowledge arising from the information in Genesis 1 (and in 5, too) is that it doesn't just assert God's creation, it doesn't merely represent a claim that is devoid of references to the very subject of the claim, but it provides God's demonstration of what he did, and by which stands his revelation (claim) to be creator, and that we are connected to his creative act resulting in Adam and Eve.
It is by the demonstration of the effects of his creative actions that we can understand the meaning of his being creator. Without the detail, as I've touched on previously, we'd be left with the emptiness of myth. God's revelation as to his being creator has content that demonstrates what it is that his being creator entails (and thus excludes other expanatory programs for the creation as we experience it: whether the pagan myths of ancient days, or the materialist mythology of today). The creative content is not isolated from this world, the world that we experience, and exist only in some other world where we have no connection, but it is in the terms of our apprehension of the bounds of this world.
God just doesn't tell us things of such importance, he shows us. Like a good author who will not just tell us the characteristics of a character, but will show us them in the narrative, God is not content to abuse our likeness to him with an indeterminate reference to his activity as creator, he gives us a precise, detailed and (as it happens) rebuttable reference; noting that rebuttal challenges God's truthfullness, capability to communicate within our noetic frame of reference, and ultimately his being creator.
The knowledge we get from these parts of Genesis tells us real things about the real world we are in: shows us real links between us and God, and a real sequence of creation that encompases the setting of our place of encounter with God in the terms in which we know that setting: it provides epistemologic consistency and contiguity.
One of the outcomes of this is that alternative explanations are excluded; or rather, to be maintained they must exclude God's revelation. So, if one wants to say that God mixed it with materialisms great fantasy, Darwinian evolution, one has to set aside, or argue for the direct meaninglessness of God's word, or some other meaning that requires the text being given a particular extra-textual gloss.
And that is indeed what we have. But at least we can't pretend with an sustained credibility that we are representing the word of God, we have to explain why we are not. At least that signals to the hearer that we are embarking upon nonsense.
