Seven is your lucky number!

In his new commentary on Genesis, Andrew Steinmann says: 

The crafting of the table can be seen in the fondness of its use of the number seven and its multiples... (122). 

In correspondence, I asked him if he could be more specific. He responded:

The table contains 70 names listed as “sons” of Ham, Shem, Japheth or their descendants. (The Philistines are different, since they are not said to be “son,” but are part of the Casluhim “from whom came the Philippines.”) Japheth has 7 sons and 7 grandsons. Mizraim has 7 “sons.” Shem has 21 grandsons/ great-grandsons.

That septunarian pattern could be produced by starting with real, albeit larger figures, then omitting certain links or individuals to get it down to groups of seven or multiples of seven. The result of editorial selectivity. 

In the past I've noted how the seven motif is embedded in the flood account:

Take with you seven pairs of every kind of clean animal, a male and its mate, and one pair of every kind of unclean animal, a male and its mate (Gen 7:2)

and also seven pairs of every kind of bird, male and female, to keep their various kinds alive throughout the earth (Gen 7:3)

Seven days from now I will send rain on the earth for forty days and forty nights, and I will wipe from the face of the earth every living creature I have made” (Gen 7:4)

And after the seven days the floodwaters came on the earth (Gen 7:10)

In the six hundredth year of Noah’s life, on the seventeenth day of the second month—on that day all the springs of the great deep burst forth, and the floodgates of the heavens were opened (Gen 7:11)

and on the seventeenth day of the seventh month the ark came to rest on the mountains of Ararat (Gen 8:4)

He waited seven more days and again sent out the dove from the ark (Gen 8:10)

He waited seven more days and sent the dove out again, but this time it did not return to him (Gen 8:12)

By the twenty-seventh day of the second month the earth was completely dry (Gen 8:14)

If Noah's flood is a real event, then it has a certain natural rhythm. So we wouldn't expect it to be so repetitively septunarian. As such, the seven motif in the flood account seems to be a stock number, just like forty is a stock number in Scripture. In some cases is might be due to rounding up or rounding down to seven of something. And in some cases there's no natural interval, so the interval will be stipulative. But the frequency appears to be artificial by design. 

So it's interesting to see the same motif in the Table of Nations. That kind of numerology suggests the narratives are somewhat stylized to highlight artificial septunarian patterns. Nature in the raw isn't that symmetrical. It doesn't normally operate in cycles of seven. 

There's nothing deceptive about that so long as the numbers were understood to be stock numbers, sometimes used for their symbolic connotations. It may be code language for God's control over events. Septunarian iterations clue the reader to the hidden hand of providence. Too coincidental to be sheer coincidence.  

Since we see this in the flood account as well as the Table of Nations, it has backward casting implications for the creation account. By analogy with the flood account and the Table of Nations, is the number of days in Gen 1 a stock number, too?