Exodus 34:32

ואחרי כן נגשו AND AFTERWARDS [THE CHILDREN OF ISRAEL] STEPPED NIGH — After he (Moses) had taught the elders he used again to teach the section or the single Halacha in question to the Israelites. The Rabbis have taught: How was the system of teaching? Moses used to learn the law from the mouth of the Almighty; Aaron entered and Moses taught him his lesson. Now Aaron moved away and took his seat to the left of Moses. Then his (Aaron’s) sons entered and Moses taught them their lesson. They moved away and Eleazar took his seat to the right of Moses, whilst Ithamar sat down at Aaron’s left. The elders then entered and Moses taught them their lesson. The elders moved away and took their seat at the side. Finally the whole people entered and Moses taught them their lesson. Consequently what was taught came into the possession of the whole people once, into the possession of the elders twice, into the possession of Aaron’s sons thrice and into Aaron’s possession four times etc. — as it is stated in Eruvin 54b.

וְאַחֲרֵי־כֵ֥ן נִגְּשׁ֖וּ כׇּל־בְּנֵ֣י יִשְׂרָאֵ֑ל וַיְצַוֵּ֕ם אֵת֩ כׇּל־אֲשֶׁ֨ר דִּבֶּ֧ר יְהֹוָ֛ה אִתּ֖וֹ בְּהַ֥ר סִינָֽי׃

And afterwards all the children of Yisra᾽el came near: and he gave them in commandment all that the Lord had spoken with him in mount Sinay.