Kiddushin 30a
קידושין ל׳ א — ד"ה תָּנוּ רַבָּנַן
Kiddushin 30a:15
The sages discuss the duty to teach Torah to children and the pedagogical importance of making Torah words sharp and well-organized, relevant to developing knowledge through questions and answers.
תָּנוּ רַבָּנַן: ״וְשִׁנַּנְתָּם״, שֶׁיְּהוּ דִּבְרֵי תוֹרָה מְחוּדָּדִים בְּפִיךְ, שֶׁאִם יִשְׁאַל לְךָ אָדָם דָּבָר אַל תְּגַמְגֵּם וְתֹאמַר לוֹ, אֶלָּא אֱמוֹר לוֹ מִיָּד, שֶׁנֶּאֱמַר:
§ The Sages taught: The verse states: “And you shall teach them diligently [veshinnantam]” (Deuteronomy 6:7). The root shin, nun, nun, of veshinnantam should be understood as meaning sharp, i.e., that matters of Torah should be sharp and clear in your mouth, so that if a person asks you something, do not stutter in uncertainty and say an uncertain response to him. Rather, answer him immediately, as it is stated: