How old was Ishmael when Isaac was weaned?
Ishmael was approximately 18 or 19 years old when Isaac was weaned. The chronology indicates Isaac was five years old at weaning, which places Ishmael at the end of his teen years, no longer a little child. Thus, Ishmael was about 18 or 19 at that event.
Les explains that chronologically Isaac had to be five years old when he was weaned. That timing places Ishmael at about 18 or 19 years old, meaning he was no longer a little child but at the end of his teen years. The context notes this as part of the account of Hagar and Ishmael being sent away, with God instructing Hagar to return to Sarah's tent.