And Ishmael his son was thirteen years old, when he was circumcised in the flesh of his foreskin.
All Commentaries on Genesis 17:25 Go To Genesis 17
Ambrose of Milan
AD 397
Even the fact that Ishmael was circumcised in his thirteenth year is for an obvious reason, because one who is beginning to be sexually active should trim the ardor of his passion, so as to abstain from illicit unions and limit himself to a legitimate union only. .
