For example, John Millam writes, "At the time of David, there were three head temple musicians, one from each of the 3 divisions of the Levites. There is Heman of the Kohathite division (verses 33-38), Asaph of the Gershonite division (verses 39-42), and Ethan of the Merarite division (verses 44-47). In each case, the genealogies start with Levi, who was the father of Kohath, Gershon, and Merari and ancestor of these three men. So, we have three genealogies side-by-side extending from Levi to the time of King David, yet the genealogies contain 21, 15, and 14 names respectively for exactly the same span of time. This suggests that at least the latter two genealogies are highly telescoped." That someone would believe that various family generations correspond chronologically leaves me aghast. My father was almost the same age as my wife's maternal grandfather, and my maternal grandfather was old enough to have been a grandfather of my wife's grandfather. Three of my father's great-grandfathers were Civil War veterans. A pastor friend who was only a few years older than my father was the SON of a Confederate veteran. Genealogies just don't correspond the way Millam seems to think, and such gaps as he supposes are merely imaginary without any supporting evidence.
Many Bible students have tried to add thousands of years to the chrono-genealogy of Genesis chapter 5, hoping to increase the earth's age to something that satisfies some scientists and their sycophants. It doesn't work. Of all the explanations proffered for gaps in Genesis 5, none can offer any reasonable explanation of why the writer would even bother with a chronology here if he is merely relating genealogy.
It is interesting that the narrative supplies extra information that ties certain sons directly to their fathers, without any gaps.
- Genesis 4:25-26 And Adam knew his wife again; and she bare a son, and called his name Seth: For God, said she, hath appointed me another seed instead of Abel, whom Cain slew. And to Seth, to him also there was born a son; and he called his name Enos: then began men to call upon the name of the Lord.
- Genesis 5:3 And Adam lived an hundred and thirty years, and begat a son in his own likeness, and after his image; and called his name Seth:
- Genesis 5:28-29 And Lamech lived an hundred eighty and two years, and begat a son: And he called his name Noah, saying, This same shall comfort us concerning our work and toil of our hands, because of the ground which the Lord hath cursed.
- Jude 14 And Enoch also, the seventh from Adam, prophesied of these, saying, Behold, the Lord cometh with ten thousands of his saints, (Enoch is the 7th generation from Adam in Genesis 5)
The best approach is to accept the text as written and let the scientific chips fall where they may.