Recently, we’ve been discussing lungs. Specifically, which lung defects are unsurvivable and therefore render an animal a treifa — no longer kosher. We’ve looked at discolorations, punctures and, today, growths:
Rabba bar bar Hana asked Shmuel: If the lung grew cysts full of pus, what is the halakhah?
Shmuel said to him: The animal is kosher.
Rabba bar bar Hana said to him: I also say so, except that the students doubt the matter, as Rav Mattana says: If the cyst was full of pus, the animal is a treifa; if it was full of clear fluid, it is kosher.
Shmuel said to him: That halakhah of Rav Mattana was stated with regard to a cyst on the kidney.
This chapter is packed with anecdotes, perhaps because checking a slaughtered animal to confirm it is kosher is an intricate process — with a great deal of ambiguity. Even the most skilled rabbis required consultation with others.
Here, Rabba bar bar Hana asks Shmuel a question for which he’s already formulated an answer, because he’s looking for backup. Rabba bar bar Hana believes that cysts full of pus on the lung would not make an animal a treifa, but his students side with Rav Mattana, who rules otherwise. Perhaps the weight of Shmuel’s ruling alone would have been sufficient to convince Rabba bar bar Hana’s students, even if it did conflict with Rav Mattana’s position. But Shmuel has something even better: an explanation that reconciles their opinions. Rav Mattana ruled cysts full of pus are disqualifying with regard to kidneys, but said nothing about cysts on lungs. We can’t extrapolate from one organ to another. Therefore, cysts on lungs are not disqualifying.
The Gemara proceeds with a story:
Rabbi Yitzhak bar Yosef was walking after Rabbi Yirmeya in the butchers’ market. He saw lungs that were full of cysts.
He said to Rabbi Yirmeya: Doesn’t the master desire a piece of meat?
Rabbi Yirmeya said to him: I have no money.
Rabbi Yitzhak bar Yosef said to him: I will buy them for you on credit.
Rabbi Yirmeya said to him: What can I do for you? As when people came before Rabbi Yohanan with such lungs, he would send them before Rabbi Yehuda, son of Rabbi Shimon, who would instruct them in such cases in the name of Rabbi Elazar, son of Rabbi Shimon, to permit. But Rabbi Yohanan himself does not hold accordingly.
As mentioned above, many of the rabbis were plagued by uncertainty around ruling slaughtered animals either kosher or not, and they hoped to receive confirmation from their colleagues. Here, Rabbi Yitzhak bar Yosef wishes to learn from Rabbi Yirmeya’s behavior how he rules: Are the lungs full of cysts kosher or treif? Rabbi Yirmeya, however, is evasive. We eventually discover why: Rabbi Yohanan, who was Rabbi Yirmeya’s teacher, did not permit animals with cysts on the lungs. However, when people came before him with such animals looking for a ruling, rather than telling them the animal was unkosher, he would send them to a colleague who ultimately permitted the meat.
This is a bit puzzling: If Rabbi Yohanan truly believes lungs with cysts disqualify an animal, how could he send people off to receive a falsely permissive ruling? Rashi clarifies: Rabbi Yohanan wasn’t comfortable ruling that such lungs were kosher, since he hadn’t learned a ruling from his own teacher on the matter, but he also wasn’t confident they were unkosher. Therefore, while he himself wasn’t comfortable giving a permissive ruling or consuming them, he didn’t perceive it as a violation to direct people towards someone who would rule permissively.
This is a good example of the kind of halakhic ambivalence that appears throughout our text. There are some matters where the halakhah isn’t clear because multiple rabbis confidently present conflicting arguments, and we aren’t certain in accordance with whom we should rule. And there are some matters where the rabbis themselves were uncertain. While they often default to strictness in uncertain cases (such as Rabbi Yohanan eschewing meat with lung cysts), this personal stringency is not the same as issuing a prohibitive ruling.
Read all of Chullin 48 on Sefaria.
This piece originally appeared in a My Jewish Learning Daf Yomi email newsletter sent on June 17, 2026. If you are interested in receiving the newsletter, sign up here.
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