Kiddushin 29a
קידושין כ״ט א — ד"ה תְּנֵינָא לְהָא דְּתָנוּ רַבָּנַן
Kiddushin 29a:10
Chachmei Bavel state that a father must circumcise and redeem his son, teach him Torah and a trade, arrange his marriage, and, according to some, teach him to swim; Rabbi Yehuda warns that failing to teach a trade is effectively like teaching banditry, since the son may otherwise resort to theft for a livelihood.
תְּנֵינָא לְהָא דְּתָנוּ רַבָּנַן: הָאָב חַיָּיב בִּבְנוֹ לְמוּלוֹ, וְלִפְדוֹתוֹ, וּלְלַמְּדוֹ תּוֹרָה, וּלְהַשִּׂיאוֹ אִשָּׁה, וּלְלַמְּדוֹ אוּמָּנוּת. וְיֵשׁ אוֹמְרִים: אַף לַהֲשִׁיטוֹ בַּמַּיִם. רַבִּי יְהוּדָה אוֹמֵר: כֹּל שֶׁאֵינוֹ מְלַמֵּד אֶת בְּנוֹ אוּמָּנוּת – מְלַמְּדוֹ לִיסְטוּת. לִיסְטוּת סָלְקָא דַּעְתָּךְ? אֶלָּא: כְּאִילּוּ מְלַמְּדוֹ לִיסְטוּת.
The Gemara comments: According to this interpretation, we learn in this mishna that which the Sages taught in a baraita: A father is obligated with regard to his son to circumcise him, and to redeem him if he is a firstborn son who must be redeemed by payment to a priest, and to teach him Torah, and to marry him to a woman, and to teach him a trade. And some say: A father is also obligated to teach his son to swim. Rabbi Yehuda says: Any father who does not teach his son a trade teaches him banditry [listut]. The Gemara expresses surprise at this statement: Can it enter your mind that he actually teaches him banditry? Rather, the baraita means that it is as though he teaches him banditry. Since the son has no profession with which to support himself, he is likely to turn to theft for a livelihood. This baraita accords with Rav Yehuda’s interpretation of the mishna.

