EXOD266 Where do we learn that his student's honor should be as dear to a person as his own? (Pirkei Avot, Perek IV, mishnah 15) Let all men learn it from Moses our Master: for he said to Joshua, "Choose for us men [and go forth to battle with Amalek]" [this verse]; it does not state "Choose for me," but rather "Choose for us," indicating that he ranked Joshua as himself; he equated his own honor with that of Joshua, although he was the master and Joshua was his disciple. Now, where do we learn that the honor of one's fellow should be as dear to him as his master's?--From the verse, "and Aaron said to Moses, O my lord" (Numbers 12:11). Now, was not his brother [Moses] younger than he? Nevertheless he ranked him as his master. And where do we learn that the honor of one's master should be as dear to him as the honor of Heaven, the honor of the Divine Presence? -- for it is stated, "and Joshua the son of Nun, the attendant of Moses since his youth, answered and said: My Lord Moses, confine them." (Numbers 11:28). He ranked him equal with the Divine Presence [for he used the same form of address: My lord] Avoth d'R. Nathan A27.