Genesis 4:18
And unto Enoch was born Irad: and Irad begat Mehujael: and Mehujael begat Methusael: and Methusael begat Lamech.
And unto Enoch was born Irad,.... But of neither of them is any other mention made, either in sacred or profane history; nor is it said how old Enoch was when Irad was born, nor how long he lived after; as is recorded of Adam, Seth, and their posterity:
and Irad begat Mehujael, and Mehujael begat Methusael; of whom also we have no other account;
and Methusael begat Lamech; and it seems for the sake of Lamech that the genealogy of Cain's posterity is described and carried down thus far, some things being to be taken notice of concerning him. The names of the immediate posterity of Genos or Cain, according to Sanchoniatho, and, as Philo Byblius {l} has translated them, were light, fire, and flame; who found out fire by rubbing pieces of wood together, and taught the use of it, from whence they seem to have their names. These begat sons that exceeded others in bulk and height, whose names were given to the mountains they first possessed, and from them were called Cassius, Libanus, Antilibanus, and Brathy; and of them were begotten Memrumus and Hypsuranius, so called by their mothers, women, who, without shame, lay with everyone they could meet with; of these came Agreus and Halieus, the inventors of fishing and hunting; and these seem to answer to the generations from Cain to Lamech; and it is no wonder Moses should take no more notice of such a set of men; which, according to their own historian, deserved but little regard.
{l} Apud Euseb. Praepar. Evangel. l. 1. p. 34, 35.