מדרש אויף במדבר 4:10

“They shall take a cloth of sky-blue wool, and cover the candelabrum of the illumination, and its lamps and its tongs” (Numbers 4:9).
“They shall take a cloth of sky-blue wool, and cover the candelabrum of the illumination” (Numbers 4:9) – the candelabrum, too, because it stands in the Sanctuary, it and all its utensils that enter there were covered with a cloth of sky-blue wool. That is what is written: “They shall take a cloth of sky-blue wool and cover…” Regarding the candelabrum, one would not separate between it and its utensils. Then they would cover it and all its utensils with a covering of taḥash hide and place it on a pole, because it did not have staves with which they would carry it. That is what is written: “They shall place it and all its utensils [into a covering of the hide of a taḥash, and shall place it on a pole]” (Numbers 4:10).

(Numb. 4:17-48:) THEN THE LORD SPOKE UNTO MOSES AND UNTO AARON, SAYING: DO NOT CUT OFF THE TRIBE OF THE KOHATHITE FAMILIES <FROM THE LEVITES>. This text is related (to Prov. 22:22): DO NOT ROB THE IMPOVERISHED BECAUSE HE IS IMPOVERISHED. R. Tanhuma bar Abba said:¹³⁶Tanh., Numb. 1:22. R. Levi said: DO NOT ROB THE IMPOVERISHED BECAUSE HE IS IMPOVERISHED. This refers to the lupine¹³⁷Gk.: thermos (“hot”). which arrives with the dessert. One should not say: There are nuts and dates before me. I will say <the blessing> over them and leave the lupine alone. The Holy One said (ibid.): DO NOT ROB THE IMPOVERISHED BECAUSE HE IS IMPOVERISHED. R. Hezekiah and R. Jeremiah bar Abba said in the name of R. Johanan: It is with reference to everyone who does not say something in the name of the one who said it that the text says (ibid.): DO NOT ROB THE IMPOVERISHED BECAUSE HE IS IMPOVERISHED.¹³⁸See Avot 6:3. So when a person hears something, it is necessary to cite it in the name of the one who <originally> said it, even though <doing so takes up> more than a third of a law (halakhah). Thus our masters have taught (in Pe'ah 2:6): R. NAHUM THE SCRIBE¹³⁹Livlar. Cf. Lat.: libellaris (“documentary”); libellarius (“relating to a written rental contract”); librarius (“scribe,” “copyist”). SAID: I HAVE RECEIVED FROM R. MAY'ASHA, WHO RECEIVED [FROM ABBA, WHO RECEIVED FROM THE PAIRS (zugot),¹⁴⁰Gk.: zuga (“yokes”); cf. Lat.: juga. WHO RECEIVED] FROM THE ELDERS, A LAW (halakhah) OF MOSES FROM SINAI. So it is with reference to whoever does not say something in the name of the one who said it that the text (of Prov. 22:22) says: DO NOT ROB THE IMPOVERISHED. But everyone who does say something in the name of the one who said it brings redemption into the world.¹⁴¹Meg. 15a. From whom have you learned it? From Esther. When she heard of the matter from Mordecai, she said to Ahasuerus according to what is stated (in Esth. 2:22): AND ESTHER SPOKE TO THE KING IN THE NAME OF MORDECAI. For that reason she was worthy of having Israel be redeemed at her hands. Ergo: If you hear something, cite it in the name of the one who said it.