Genesis 4:18

18. Irad… Mehujael… Methusael Compare the similar names in the Sethite genealogy recorded in the next chapter, Jared, Mahalaleel, and Methuselah . Hence some have supposed a confusion growing out of two forms of one and the same old legend . But why may not different families have adopted similar or identical names in that as in later ages? Enoch and Lamech are names that occur in both genealogies, but the piety of the sons of Seth, bearing these names, is in notable contrast with the worldliness of Cain’s Enoch and the polygamy of Cain’s Lamech. This contrast seems to have been drawn out, as if to prevent the possibility of confounding the two genealogies.