Study Menachot folio 101B with parallel Hebrew-English text, traditional commentary, and modern study tools. Free access to Babylonian Talmud online.
the flesh of an ox that is stoned, a heifer whose neck is broken, the birds sacrificed by a metzora (see Leviticus 14:4–7), a firstborn donkey whose neck was broken, and meat cooked together with milk are all susceptible to the ritual impurity of food, despite the fact that they are forbidden for c
R' Shimon says: None of them are susceptible to the ritual impurity of food, since they are all items from which it is prohibited to derive benefit, and they are therefore not considered food. And R' Shimon concedes with regard to meat cooked together with milk that it is susceptible to the ritual
And Rav Asi said that R' Yoḥanan said: What is the reason for R' Shimon’s opinion that an item from which it is prohibited to derive benefit is not susceptible to impurity of food? It is because it is stated: “All food which may be eaten [ha’okhel asher ye’akhel], that on which water comes, shall b
R' Oshaya explains how this can be applied to piggul: A meal offering that one rendered piggul is also food that you are not able to feed to others, as it is prohibited to derive benefit from it. Consequently, it is not susceptible to the ritual impurity of food according to R' Shimon.
The Talmud asks: If so, why doesn’t he also derive that meat cooked in milk is susceptible to impurity because it is food that you may feed to others, as R' Shimon maintains that it is permitted to derive benefit from meat and milk cooked together?