It remains to mention the sons of Shem, Noah's eldest son; for to him this genealogical narrative gradually ascends from the youngest. But in the commencement of the record of Shem's sons there is an obscurity which calls for explanation, since it is closely connected with the object of our investigation. For we read, "Unto Shem also, the father of all the children of Heber, the brother of Japheth the elder, were children born."[235] This is the order of the words: And to Shem was born Heber, even to himself, that is, to Shem himself was born Heber, and Shem is the father of all his children. We are intended to understand that Shem is the patriarch of all his posterity who were to be mentioned, whether sons, grandsons, great-grandsons, or descendants at any remove. For Shem did not beget Heber, who was indeed in the fifth generation from him. For Shem begat, among other sons, Arphaxad; Arphaxad begat Cainan, Cainan begat Salah, Salah begat Heber. And it was with good reason that he was named first among Shem's offspring, taking precedence even of his sons, though only a grandchild of the fifth generation; for from him, as tradition says, the Hebrews derived their name, though the other etymology which derives the name from Abraham (as if _Abrahews_) may possibly be correct. But there can be little doubt that the former is the right etymology, and that they were called after Heber, _Heberews_, and then, dropping a letter, Hebrews; and so was their language called Hebrew, which was spoken by none but the people of Israel among whom was the city of God, mysteriously prefigured in all the people, and truly present in the saints. Six of Shem's sons then are first named, then four grandsons born to one of these sons; then it mentions another son of Shem, who begat a grandson; and his son, again, or Shem's great-grandson, was Heber. And Heber begat two sons, and called the one Peleg, which means "dividing;" and Scripture subjoins the reason of this name, saying, "for in his days was the earth divided." What this means will afterwards appear. Heber's other son begat twelve sons; consequently all Shem's descendants are twenty-seven. The total number of the progeny of the three sons of Noah is seventy-three, fifteen by Japheth, thirty-one by Ham, twenty-seven by Shem. Then Scripture adds, "These are the sons of Shem, after their families, after their tongues, in their lands, after their nations." And so of the whole number: "These are the families of the sons of Noah after their generations, in their nations; and by these were the isles of the nations dispersed through the earth after the flood." From which we gather that the seventy-three (or rather, as I shall presently show, seventy-two) were not individuals, but nations. For in a former passage, when the sons of Japheth were enumerated, it is said in conclusion, "By these were the isles of the nations divided in their lands, every one after his language, in their tribes, and in their nations."