As mentioned previously, the old critical scholarly view that Genesis was merely a demythologised version of Enuma Elish and Atrahasis has fallen out of favour. However, the conservative view that the Babylonian stories are corrupted versions of Genesis is likewise hard to defend as the Genesis story as written dates well after these Babylonian tales. In their original form, they stretch back to the second millennium BCE, well before the 1st millennium BCE date for Genesis. The OT scholar Gordon Wenham is simply echoing what OT scholars, irrespective of their view on how the OT was compiled accept – the Genesis account is compiled from a number of sources:
Furthermore, the general parallel between Gen 1–11 and the Sumerian flood story and the particular Babylonian parallels with the flood story suggest that the thematic unity of this biblical material antedates J or P. Most of the narratives in Genesis are so vivid and well told that it seems high-handed to deny their substantial unity and split them up into various much less fetching parts.
Nevertheless, within the gripping narratives that characterize most of the book, certain sections stand out as quite different: the genealogies in chaps. 5 and 11, the table of nations in chap. 10, and the war against the eastern kings in chap. 14 have a totally different feel about them. It seems likely that they come from a source or sources different from the surrounding materials. (Most of chaps. 5, 10, and 11 are traditionally P, and 14 is unattached). And when Gen 1–11 is compared with chaps. 12–50, a striking difference emerges: chaps. 1–11 are full of parallels with Near Eastern tradition, so that it looks as though Genesis is reflecting these oriental ideas both positively and negatively….The opening chapters use and modify stories well diffused throughout the ancient world, whereas the patriarchal stories with their focus on the origins of the nations may be presumed to have been passed down within the Israelite tribes. It seems likely then that a number of written and oral sources were used to compile Genesis.1
Arguing about whether Genesis depends on the Babylonian narratives or whether these narratives are corrupted versions of Genesis misses the point – both accounts most likely share a common ancestor. Wenham again:
In fact, the Atrahasis epic from the early second millennium shows that the basic plot of Gen 1–11 was already known then. The Atrahasis epic tells of the creation of mankind, then of various divine judgments on him, culminating in the flood which destroyed all but Atrahasis and his family, who escaped in a boat. As in Genesis they offer a sacrifice on leaving the ark. Clearly the Atrahasis epic shows that creation and flood were already part of a coherent story of world origins before Genesis was composed.2