After the nine generations from Adam to Lamech, we reach the climax of the genealogy. It’s Noah! The last verse of Genesis five says, “After Noah was 500 years old, Noah fathered Shem, Ham, and Japheth.” According to Cassuto, we have all this pre-flood information because Noah preserved it for us. The genealogies and all the advances made before the flood were preserved for the post-flood generations. He writes, “The teachings and occupation of Jabal, as well as those of his brothers, were apparently transmitted to mankind after the Flood through Noah and his sons. Similarly, there is a Babylonian story about books that were hidden before the Flood in the ground beneath the City of the Sun, Sippar, in order to save them from the water, and were disinterred after the Flood.”[1]
At the beginning of Genesis chapter five, we saw the mention of “The book” of the genealogies of Seth. The word “Sepher” (Book in Hebrew) implies that Moses had a source from which to draw his information. The details of the accounts of Chapter five were preserved for us by Noah and his descendants. It’s also essential to notice that the life spans of these patriarchs were contemporaneous. Speiser says, “Finally, prodigious as are the lifespans of the individual patriarchs, they are dovetailed to such an extent that the total elapsed time adds up to no more than 1656 years in the Hebrew version. The death of Adam must be dated to the generation of Noah’s father, Lamech. In turn, Noah himself would have witnessed the sixtieth birthday of Abraham.”[2] We owe the preservation of the pre-flood history to Shem, Ham, and Japheth. All three of these sons lived with the patriarchs mentioned in Chapter five. The point being is that we have actual source documents for the information in early Genesis. It was not tradition passed on by word of mouth and corrupted by various enhancements along a long and mysterious road to Moses. The information we have is as trustworthy as any first-hand account.
I’d expect that Shem was the primary bookkeeper. The Semites were best at keeping records. I have suggested that the comment back at the end of Chapter four at the beginning of the genealogy from Seth says, “At that time people began to call upon the name of the Lord,” really meant to “preach” about God to their fellow man. Since it is placed at the beginning of Seth’s genealogy, I expect that it refers to them and not the genealogy of Cain that preceded the comment. They were too busy building cities, domesticating animals, and making instruments of war to fool around with the idea of God. The history of man and his relationship with God was preserved through Seth’s line. They were the first to write, and the book from which Moses got the details of early Genesis came directly from them.
[1] Cassuto, U. 1998. A Commentary on the Book of Genesis: Part I, From Adam to Noah (Genesis I–VI 8). Translated by Israel Abrahams. Jerusalem: The Magnes Press, The Hebrew University.
[2] Speiser, E. A. 2008. Genesis: Introduction, Translation, and Notes. Vol. 1. Anchor Yale Bible. New Haven; London: Yale University Press.