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תָּנוּ רַבָּנַן, כֵּיצַד סֵדֶר מִשְׁנָה: מֹשֶׁה לָמַד מִפִּי הַגְּבוּרָה. נִכְנַס אַהֲרֹן, וְשָׁנָה לוֹ מֹשֶׁה פִּירְקוֹ, נִסְתַּלֵּק אַהֲרֹן וְיָשַׁב לִשְׂמֹאל מֹשֶׁה. נִכְנְסוּ בָּנָיו, וְשָׁנָה לָהֶן מֹשֶׁה פִּירְקָן. נִסְתַּלְּקוּ בָּנָיו, אֶלְעָזָר יָשַׁב לִימִין מֹשֶׁה, וְאִיתָמָר לִשְׂמֹאל אַהֲרֹן. רַבִּי יְהוּדָה אוֹמֵר: לְעוֹלָם אַהֲרֹן לִימִין מֹשֶׁה חוֹזֵר. נִכְנְסוּ זְקֵנִים וְשָׁנָה לָהֶן מֹשֶׁה פִּירְקָן. נִסְתַּלְּקוּ זְקֵנִים, נִכְנְסוּ כׇּל הָעָם וְשָׁנָה לָהֶן מֹשֶׁה פִּירְקָן. נִמְצְאוּ בְּיַד אַהֲרֹן אַרְבָּעָה, בְּיַד בָּנָיו שְׁלֹשָׁה, וּבְיַד הַזְּקֵנִים שְׁנַיִם, וּבְיַד כׇּל הָעָם אֶחָד. נִסְתַּלֵּק מֹשֶׁה וְשָׁנָה לָהֶן אַהֲרֹן פִּירְקוֹ. נִסְתַּלֵּק אַהֲרֹן שָׁנוּ לָהֶן בָּנָיו פִּירְקָן. נִסְתַּלְּקוּ בָּנָיו, שָׁנוּ לָהֶן זְקֵנִים פִּירְקָן. נִמְצָא בְּיַד הַכֹּל אַרְבָּעָה. מִכָּאן אָמַר רַבִּי אֱלִיעֶזֶר: חַיָּיב אָדָם לִשְׁנוֹת לְתַלְמִידוֹ אַרְבָּעָה פְּעָמִים. וְקַל וָחוֹמֶר, וּמָה אַהֲרֹן שֶׁלָּמַד מִפִּי מֹשֶׁה, וּמֹשֶׁה מִפִּי הַגְּבוּרָה — כָּךְ, הֶדְיוֹט מִפִּי הֶדְיוֹט — עַל אַחַת כַּמָּה וְכַמָּה.
The Gemara continues to discuss methods of Torah study. The Sages taught the following baraita: What was the order of teaching the Oral Law? How was the Oral Law first taught? Moses learned directly from the mouth of the Almighty. Aaron entered and sat before him, and Moses taught him his lesson as he had learned it from God. Aaron moved aside and sat to the left of Moses. Aaron’s sons entered, and Moses taught them their lesson while Aaron listened. Aaron’s sons moved aside; Elazar sat to the right of Moses and Itamar sat to the left of Aaron. Rabbi Yehuda disagreed with the first tanna with regard to the seating arrangements and said: Actually, Aaron would return to sit to the right of Moses. The elders entered and Moses taught them their lesson. The elders moved aside, and the entire nation entered and Moses taught them their lesson. Therefore, Aaron had heard the lesson four times, his sons heard it three times, the elders heard it twice, and the entire nation heard it once. Moses then departed to his tent, and Aaron taught the others his lesson as he had learned it from Moses. Aaron then departed and his sons taught the others their lesson. His sons then departed and the elders taught the rest of the people their lesson. Hence everyone, Aaron, his sons, the elders and all the people, heard the lesson taught by God four times. From here Rabbi Eliezer said: A person is obligated to teach his student his lesson four times. And it follows by way of an a fortiori inference: If Aaron, who learned from Moses himself, and Moses had received the Torah directly from the mouth of the Almighty, needed this regimen; an ordinary student learning from the mouth of an ordinary teacher, how much more so must he review his studies four times.