How Old Was Isaac?
Jonathan Kirsch suggests that Ishmael sexually abused a younger Isaac (Insight, “What Did Sarah See?” BR 14:05). One statement puzzles me: the “deeply enigmatic scene in which we find the 15-year-old Ishmael at play with his 5-year-old half-brother…”
The 15-year-old Ishmael I can gather from Genesis 16:16, 17:17, 21, 25 and 21:5. But how does Kirsch deduce that at his weaning (Genesis 21:8) Isaac was five years old?
Jonathan Kirsch responds:
The age of Isaac on the day of his weaning, which is not specified in the Bible, is the subject of surmise in the sources that I consulted in writing my book The Harlot by the Side of the Road. Gerald Larue suggests that Isaac “would have been three or four years of age at that time” (Sex and the Bible [Prometheus Books, 1983], p. 99). E.A. Speiser allows that Isaac may have been even older: “To this day, weaning may take place in the Near East as late as at three years or more; it is often followed by a celebration” (E.A. Speiser, Genesis, Anchor Bible 1 [Garden City, NY: Doubleday, 1987], p. 155).