First we need to establish the goal of these accounts before we make a decision about its literalness and does the goal still hold even if in a non-literal form? If the latter is true, the account may have historical inaccuracy, but if we establish that the historical accuracy was not a high ranking goal then perhaps approaching it historical is the wrong approach.
For example in the creation account light is spoken into darkness (before the sun is made) that triggers a transformation process that ends in rest. This is without question a redemptive metaphor and light being spoken into darkness is one of the most used metaphors in the Bible. Christ calls himself even the light of the world. So what's more important that the creation took 6 literal days or that God sends light to a broken informed darkness? Redemptively speaking the literal event have little meaning but the redemptive metaphor is wholly useful and packed full with meaning even for today.
The flood to Moses, who is traditionally said to pen the account, is about 800 years. Modern academia shows much later dates. If the account survived through oral tradition which is the most likely scenario how much of the account resembles the factual detail and does it even matter?
The account comes on the heels of this odd remark about angels (sons of God) intermixing with humans (daughters of men) and created some sort of super race (nephilim) so we're definitely in myth territory. Then decision for the flood happens. It's also written in a chiastic structure which already shows us some massaging of the account was applied. The angels intermixing shows us how corrupted the earth has become and it serves as a pretext for the flood. The flood shows us a salvation event through one man/family to rescue the whole world which foreshadows Christ. It sets up an account to an ancient people group some 800 years after the fact to understand and grasp at more concrete levels then dealing with abstracts that is later unravailed to reveal its depth while using an account thst other cultures have mythologies about.
If the account's primary goal is to foreshadow Christ to show that through Christ all are saved then the account alone serves that propose. What we have in the Bible is no less than 800 years after the fact so it's literal impact is lost and meaningless to the context it is delivered to. There was no flood survivors, there was no living record of it happening or knowledge of someone who experienced it. History doesn't erase itself after x amount of time, and I get that, but because the biblical account shows little impact of before and after its difficult to fit it into a historical landscape or how things developed from its result.
For these reasons the literalness of the account has only anecdotal impact but nothing with any firm support. There are analogous accounts from other culturals so maybe some sort of flood event happened but I see the biblical account's redemptive goal to be superior to its literalness with the case of the flood. I don't take offence to the details as they are but a literal goal is not why I read it.
I appreciate what you've shared here, but as a philosopher I flip the matrix and put theology, and its resulting faith, last as an
a posteriori emergent outcome. So, you and I will go at this a bit differently. And that's ok.
Personally, I want to know who the author of the Biblical Flood account was, what his intended message was, and what his particular sources were from which he drew up his writings, accounts, and/or narratives. Unfortunately, much of that is very difficult to get at, if even possible. I only expect there to be fragmentary evidences, if any even exist.
With your interpretation, one has to start with the assumption that everything that has been revealed in Christ is true, and then the older material is deemed to be "explained" with purpose. However, in my approach, I only let that gate open at the end of investigation, cumulatively, not as a preliminary. I try to start with as few a priori assumptions as possible, asking question upon question along the way, and knocking on many skeptical and atheistic walls before getting to "faith," or to an understanding and acceptance of what the Biblical Flood account is in its literary essence (whether that essence is prophetic and mythic, or literal and revealed, or a mere remnant cultural surmising of a by-gone ancient era).
If there is a literary goal Moses (or other Mosaic writers) had in mind by presenting the Flood Account along with the rest of what is written in Genesis (or perhaps in consideration of the entire Pentateuch, maybe), then I need to be able to detect that
historiographically within the Torah material itself.
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