But the question is which came first, the chicken or the egg. Tangible Sumerian records are testable as to age and consistency. But there are no records from the original bible times in existence. What is the age of the existing records of the OT? The WTS says that Moses had in his possession scrolls written by Adam, Enoch, and other pre-flood individuals that Shem preserved in the Ark and passed onto his descendants that the WTS eventually became the Jews. That Moses used those scrolls to write Genesis. But we don't have those scrolls. And once again what are the oldest writings we have that back the OT?
*** it-1 pp. 919-920 Genesis, Book of ***
From where did Moses get the information he included in Genesis?
All the information contained in the book of Genesis relates to events that took place prior to Moses’ birth. It could have been received directly by divine revelation. It is obviousthat someone had to receive the information relating to the events prior to man’s creation in that way, whether Moses or someone prior to him. (Ge 1:1-27; 2:7, 8) This information and the remaining details, however, could have been transmitted to Moses by means of oral tradition. Because of the long life span of men of that period, the information could have been passed from Adam to Moses through just five human links, namely, Methuselah, Shem, Isaac, Levi, and Amram. A third possibility is that Moses obtained much of the information for Genesis from already existing writings or documents. As far back as the 18th century, the Dutch scholar Campegius Vitringa held this view, basing his conclusion upon the frequent occurrence in Genesis (ten times) of the expression (in KJ) "these are the generations of," and once "this is the book of the generations of." (Ge 2:4; 5:1; 6:9; 10:1; 11:10, 27; 25:12, 19; 36:1, 9; 37:2) In this expression the Hebrew word for "generations" is toh?le?dhohth´, and it is better rendered "histories" or "origins." For example, "generations of the heavens and of the earth" would hardly be fitting, whereas "history of the heavens and the earth" is meaningful. (Ge 2:4) In harmony with this, the German Elberfelder, the French Crampon, and the Spanish Bover-Cantera all use the term "history," as does the NewWorldTranslation. There is no doubt that even as men today are interested in an accurate historical record, so they have been from the start.
For these reasons, Vitringa and others since have understood each use of toh?le?dhohth´ in Genesis to refer to an already existing written historical document that Moses had in his possession and that he relied upon for the majority of the information recorded in Genesis. They believe that the persons named in direct connection with such ‘histories’ (Adam, Noah, Noah’s sons, Shem, Terah, Ishmael, Isaac, Esau, and Jacob) were either the writers or original possessors of those written documents. This, of course, would still leave unexplained how all such documents came to be in the possession of Moses. It also leaves unexplained why documents obtained from men who were not distinguished as faithful worshipers of Jehovah (such as Ishmael and Esau) should be the source of much of the information used. It is entirely possible that the expression "This is the history of" is simply an introductory phrase serving conveniently to divide off the various sections of the long overall history. Compare Matthew’s use of a similar expression to introduce his Gospel account.—Mt 1:1; see WRITING.
No definite conclusion can be arrived at, therefore, as to the immediate source from which Moses obtained the information he recorded. Rather than just by one of the methods discussed, the information may have been received by all three, some through direct revelation, some through oral transmission, some by written records. The important point is that Jehovah God guided the prophet Moses so that he wrote by divine inspiration.—2Pe 1:21.
The material was to serve as an inspired guide to future generations. It was to be read to the people on frequent occasions (De 31:10-12; 2Ki 23:2, 3; Ne 8:2, 3, 18), and Israel’s kings were to take instructions from it.—De 17:18, 19.