daf bit: Kiddushin 29

Some commandments are binding on men but not on women, among them the following obligations to his son: to circumcise him, to redeem him, to teach him torah, to find him a wife, and to teach him a craft. Some say: and to teach him to swim. Rabbi Yehudah said that a man who does not teach his son a craft teaches him brigandry. (29a)