I am reading the wonderful collection of sichos of the Rebbe זי"ע called Torah Studies edited by Rav Jonathan Sacks ז״ל. In the lecture on the parashah of Chayei Sara, the Rebbe says "the reward for the creation of spiritual benefits is ascribed to the deceased", and the note refers us to Pirkei Avot, 5:8. But unfortunately, there is no mention of this issue in the quoted passage of the Pirkei Avot. Does someone know where to locate the place in the Pirkei Avot where this issue is discussed? Thank you very much for your help in advance.
It's a misprint in the original sicha (footnote 40). It should be Avot 5:18:
Moses was righteous and caused the multitudes to be righteous, [therefore] the righteousness of the multitudes is hung on him