Consequently it does not at all appear whether he who is named as the son was himself the first begotten. Nay, since it is incredible that those fathers were either so long in attaining puberty, or could not get wives, or could not impregnate them, it is also incredible that those sons were their first-born. But as the writer of the sacred history designed to descend by well-marked intervals through a series of generations to the birth and life of Noah, in whose time the flood occurred, he mentioned not those sons who were first begotten, but those by whom the succession was handed down.
Let me make this clearer by here inserting an example, in regard to which no one can have any doubt that what I am asserting is true. The evangelist Matthew, where he designs to commit to our memories the generation of the Lord’s flesh by a series of parents, beginning from Abraham and intending to reach David, says, “Abraham begat Isaac;” why did he not say Ishmael, whom he first begat? Then “Isaac begat Jacob;” why did he not say Esau, who was the first-born? Simply because these sons would not have helped him to reach David. Then follows, “And Jacob begat Judah and his brethren:” was Judah the first begotten? “Judah,” he says, “begat Pharez and Zara;” yet neither were these twins the first-born of Judah, but before them he had begotten three other sons. And so in the order of the generations he retained those by whom he might reach David, so as to proceed onwards to the end he had in view. And from this we may understand that the antediluvians who are mentioned were not the first-born, but those through whom the order of the succeeding generations might be carried on to the patriarch Noah. We need not, therefore, weary ourselves with discussing the needless and obscure question as to their lateness of reaching puberty.