Pesachim 62B

בטומאת בשר ⁠— היכא הותרה? אלא פשיטא בטומאת גברי, והיכא הותרה מכללה ⁠— בציבור.

impurity of the meat, where is it permitted to eat impure sacrificial meat? Rather, it is obvious that the baraita is talking here about impurity of the people. And where is an allowance made from its rule? It is made in the community; when the majority of the community is ritually impure, it is permitted to offer the Paschal lamb and eat it while impure.

רישא בטומאת בשר, סיפא בטומאת גברי! אין ⁠— שם טומאה קפריך.

The Talmud expresses surprise again: It turns out then that the first clause of the baraita is referring to impurity of the meat, while the latter clause relates to impurity of the people. The Talmud answers: Yes, and there is no difficulty, as the baraita argues from the general category of impurity without necessarily relating to the same type of impurity.

ואיבעית אימא: כולה בטומאת בשר, והיכא הותרה ⁠— בטומאת פסח, דתנן: פסח הבא בטומאה ⁠— נאכל בטומאה, שלא בא מתחילתו אלא לאכילה.

And if you wish, say a different answer: The entire baraita is referring to impurity of the meat, and where is it permitted to eat impure sacrificial meat? It is permitted in a case of the impurity of the Paschal lamb, as we learned in a Mishnah: A Paschal lamb that comes in impurity, e.g., when the majority of the community is ritually impure and the offering may be brought in impurity, may also be eaten in impurity, as from the very outset it came only to be eaten. This is unlike the law with regard to other offerings that are brought in impurity; their blood is sprinkled on the altar, but their meat may not be eaten. Consequently, even the prohibition to consume impure sacrificial meat is permitted under certain circumstances.