GEMARA: The mishna cited a dispute between Rabbi Yosei and the Rabbis, in which Rabbi Yosei ruled that one who vows that milk is forbidden to him is prohibited from eating whey as well. And the Gemara raises a contradiction between this ruling and Rabbi Yosei’s opinion in a later mishna (53b): One who vows that lentils are forbidden to him is prohibited from eating ashishim, a dish made from lentils. But Rabbi Yosei permits it. Apparently, Rabbi Yosei holds that if the forbidden food changes in form, it is permitted, contrary to his opinion with regard to whey.

The Gemara answers: This is not difficult. The opinion of this Sage is in accordance with the custom of his locale, and the opinion of that Sage in accordance with the custom of his locale. In the Rabbis’ locale they call milk, milk and whey, whey, whereas in Rabbi Yosei’s locale they also call whey, milk whey. In the latter location, the word milk is used in reference to whey, and therefore one who vows there that milk is forbidden to him is prohibited from eating whey as well.

It is taught in a baraita: One who vows that milk is forbidden to him is permitted to partake of whey. One who vows that whey is forbidden to him is permitted to partake of milk. One who vows that milk is forbidden to him is permitted to eat cheese. One who vows that cheese is forbidden to him is permitted to partake of milk. One who vows that gravy is forbidden to him is permitted to eat sediments of boiled meat. One who vows that sediments of boiled meat are forbidden to him is permitted to eat gravy. If one said: This piece of meat is hereby forbidden to me, he is prohibited from eating it, and from its gravy, and from its sediments.

One who vows: Wine is forbidden to me, is permitted to eat a cooked dish that has the flavor of wine. However, if he said: This wine is konam for me, and for that reason I will not taste it, and the wine fell into a cooked dish, if the dish contains an amount of the wine that gives it flavor, it is forbidden.

MISHNA: One who vows that grapes are forbidden to him is permitted to partake of wine. One who vows that olives are forbidden to him is permitted to partake of oil. However, if one said: Olives and grapes are konam for me, and for that reason I will not taste these items, he is prohibited from tasting them and the wine and oil that emerge from them.

GEMARA: With regard to the last ruling in the mishna, that one who vows: Olives and grapes are konam for me, and for that reason I will not taste these items, he is prohibited from tasting them and the wine and oil that emerge from them, Rami bar Ḥama raises a dilemma: Is it specifically because he said these, i.e., he referred to specific olives or grapes, or is it specifically because he said: For that reason I will not taste, i.e., he referred not to eating but to tasting?

The Gemara asks: If it enters your mind that it is specifically because he said these, why do I need the phrase: That I will not taste? The Gemara answers: This teaches us that even if he said: That I will not taste, only if he said the word these is he prohibited from tasting oil or wine, but if he did not say the word these, he is not prohibited from doing so. The dilemma therefore cannot be resolved by inference from the phrasing of the vow in the mishna.

Rava said: Come and hear a resolution to this dilemma from the mishna below (57a): If one says: This produce is konam upon me, or: It is konam to my mouth, he is prohibited from eating their replacements and anything that grows from them. It may be inferred that liquids that emerge from them are permitted. Evidently, referring to specific produce is not sufficient to render their juice forbidden. Rather, the prohibition in the mishna is apparently due to the phrase: And for that reason I will not taste.

The Gemara refutes this proof: The same ruling as in the mishna above is true with regard to liquids that emerge from the produce; they too are forbidden. And the reason this ruling isn’t mentioned there is that it is preferable for that mishna to teach us that their replacements are forbidden just like what grows from them is forbidden, although they contain no substance of the forbidden item.

Come and hear a resolution from the continuation of that same mishna: If one says: This produce is konam upon me, and for that reason I will not eat them, or: This produce is konam upon me, and for that reason I will not taste them, he is permitted to eat their replacements and anything that grows from them. It may be inferred that liquids that emerge from them are forbidden. The Gemara rejects this argument: Since that mishna did not cite liquids that emerge from them in the first clause, it did not cite liquids that emerge from them in the latter clause either. Therefore, it cannot be inferred that liquids that come from the produce are forbidden.

Come and hear a resolution from the previous mishna (52a): Rabbi Yehuda said: There was an incident where Rabbi Tarfon prohibited me from eating even eggs that were cooked with meat. The Rabbis said to him: Indeed so, but when is this the halakha? When the one who took the vow said: This meat is forbidden to me, referring to a specific piece of meat. This is because in the case of one who vows that something is forbidden to him and it gets mixed into another food, and the latter food contains an amount of the forbidden food that gives it flavor, i.e., the prohibited food can be tasted in the permitted food, the mixture is forbidden. Evidently, referring to a specific food causes what emerges from it to be forbidden as well.

The Gemara reinterprets the dilemma: We do not raise the dilemma with regard to the word these, as using specifically this word is certainly sufficient to render the liquids that come from the produce forbidden. When we raise a dilemma, it is with regard to the phrase: That I will not taste it. Is this phrase mentioned by the mishna specifically to teach that using it in a vow is sufficient to render the juice forbidden, or is it not mentioned specifically for that purpose?

Come and hear a resolution from the mishna above (51b): If one vows: Fish or fishes are konam for me, and for that reason I will not taste them, he is prohibited with regard to all of them, whether large fish or small, and whether raw or cooked. But he is permitted to taste minced sardines and to taste fish brine. The phrase: I will not taste, clearly does not render fish brine forbidden, although it contains that which emerged from fish.

Rava said: But there is no evidence from here, as the fish brine that is permitted by the mishna may be referring to brine that already emerged from them before the vow was taken, and was therefore not included in the fish that were rendered forbidden by the vow. The dilemma therefore remains unresolved.