Ruth 4:22

How can this be a true genealogy, seeing by this means four persons take up three hundred and eighty years, which were between Salmon and David, and consequently every one of them must beget a son when he was very old? Answ.

1. It is not certain that each of these was the immediate parent of him whom he is said to beget; for sometimes grandfathers are said in Scripture to beget their grandchildren, to wit, by the intervention of their immediate sons; whereof instances have been given. And sometimes in genealogies whole generations are omitted, as may appear by Ezra 7:2, compared with 1 Chronicles 6:3 and by Matthew 1:8, which might be done here for divers reasons now unknown.

2. There are many examples even in profane writers, both ancient and modern, of persons that have not only lived one hundred and twenty and one hundred and thirty years and upwards, but have been vigorous and have begotten children at above one hundred years old; and of women that have conceived and born children at the age of fifty, sixty, yea, seventy years. And therefore if it were so in these more ancient times, when men were longer lived, and under the law, when long life was expressly promised to the obedient, and in persons of strong constitutions and sober conversations, such as some of these are known to have been, and the others may justly be presumed to be such, it is not strange, nor in the least incredible.