The Gemara explains: There, the substance of the wine is a recognizable component of the fish stew; here, its substance is not a recognizable component of the pickled vegetables.

§ The mishna teaches: And minced tarit fish, and brine that does not have a kilbit fish floating in it, and ḥilak are all prohibited. The Gemara asks: What is ḥilak? Rav Naḥman bar Abba says that Rav says: This is sultanit, a type of small fish that is generally caught before its scales have developed. And for what reason is it prohibited? It is because its size causes it to be intermingled with other fish, and as a result sultanit rises out of the water with non-kosher fish when it is caught.

The Sages taught: If a fish does not currently possess scales but will grow them after a period of time, such as the sultanit and afiyatz fish, it is permitted. Likewise, if it has scales now but will shed them when it is caught and rises from the sea, such as akunas and afuna, ketasfatiyas and akhsaftiyas and otanas fish, it is permitted.

Rabbi Abbahu announced in Caesarea: Fish entrails and their eggs may be purchased from any person, as the presumption with regard to them is that they come only from Pelusium [Pilusa] and Spain [Aspamya], and non-kosher fish are not found in those areas. This is similar to that which Abaye says: These small fish [tzaḥanta] of the Bav River are permitted, as non-kosher fish are not found in that river.

The Gemara asks: What is the reason that Abaye unequivocally permitted eating these fish and was not concerned about the potential presence of non-kosher fish among them? If we say that it is due to the fact that the water flows rapidly, and these non-kosher fish, since they do not have a spinal cord, are not able to exist in a place where the water flows rapidly, as the current carries the non-kosher fish out of the Bav River, and consequently all the remaining fish are kosher, that is not the case, since we see that non-kosher fish exist in rivers with strong currents.

Rather, perhaps Abaye permitted the fish because the water is salty, and these non-kosher fish are not able to exist in a place of salty water since they do not have scales. This, too, is not the case, since we see that non-kosher fish exist in salty water. Rather, Abaye permitted the small fish in the Bav River because the mud in that river is not suitable for non-kosher fish to reproduce. The conditions in the river render it an unproductive habitat for non-kosher fish. Ravina says: Nowadays, as the government built canals between the rivers, and the Goza River and the Gamda River spill into the Bav and carry non-kosher fish there, it is prohibited to eat the small fish without thorough inspection.

The Gemara cites several other statements of amora’im that concern the halakhic status of fish. Abaye says: This creature known as the sea donkey [ḥamara deyamma] is permitted; the creature known as the sea ox [tora deyamma] is prohibited, and your mnemonic to remember this halakha is: Impure is pure, and pure is impure, i.e., the name of an animal which is non-kosher on land is kosher in the sea, and that which is kosher on land is non-kosher in the sea.

Rav Ashi said: The type of fish known as shefar nuna is permitted, and the type of fish known as kadesh nuna is prohibited, and your mnemonic to remember this halakha is: That which is holy [kodesh] is to the Lord, and not for humans. And some say that Rav Ashi said: The type of fish known as kevar nuna is prohibited, and your mnemonic is: The grave [kever] is impure like the graves of gentiles.

The Gemara relates several incidents involving Sages and their rulings with regard to fish. Rabbi Akiva happened to come to Ginzak and they brought before him a certain fish that was similar to a ḥippusha, a non-kosher aquatic creature. When he enclosed it in a basket he saw that it had scales which it shed as it struggled to escape from the basket, and he permitted it on that basis. Rav Ashi happened to come to Tamduria where they brought before him a certain fish that was similar to an eel [tzelofḥa]. He took it out and held it against the light of day and saw that there were thin scales on it, and he permitted it.

Rav Ashi also happened to come to a certain land where they brought before him a fish that was similar to a shefarnuna. He enclosed it in a white vessel and saw that it shed dark scales, which he could see against the white background of the container, and he permitted it. Rabba bar bar Ḥana happened to come to Akra DeAgma and they brought him some tzaḥanta, a dish prepared from small fish. He heard a certain man calling it batei, the name of a non-kosher sea creature.

Rabba bar bar Ḥana said to himself: From the fact that he called it batei, I can conclude from here that there is a non-kosher substance in the tzaḥanta. And he did not eat from it that night. In the morning, he examined the dish and in fact found a non-kosher substance in it. He read the following verse about himself: “No sin shall befall the righteous” (Proverbs 12:21).

§ The mishna teaches: And a sliver of ḥiltit may not be consumed, although one may derive benefit from it. The Gemara asks: What is the reason that it is prohibited? It is because they slice it with a knife on which there is presumably non-kosher residue. And even though the Master said that a prohibited substance that imparts flavor to the detriment of the mixture is permitted, that principle does not apply in this case because as a result of the sharpness of the ḥiltit, the act of slicing it with a knife sweetens, i.e., enhances, the taste of the non-kosher residue. And there-fore it is like a prohibited substance that imparts flavor to the enhancement of the mixture, and it is prohibited.

The Gemara relates that the gentile slave of Rabbi Levi would sell ḥiltit, and it was permitted to purchase it from him as he was the slave of a Sage. When Rabbi Levi passed away, they came before Rabbi Yoḥanan and said to him: Now that Rabbi Levi has passed, what is the halakha with regard to whether or not it is permitted to purchase ḥiltit from his gentile slave? Rabbi Yoḥanan said to them: The slave of a ḥaver, one devoted to the meticulous observance of mitzvot, especially halakhot of ritual purity, teruma, and tithes, is as a ḥaver himself, and therefore it is permitted to buy ḥiltit from him.

The Gemara relates another incident that involves the status of a ḥaver and his household. Rav Huna bar Minyumi purchased sky-blue dye [tekhelta] from the people of the household, i.e., the wife, of Rav Amram the pious. One may purchase sky-blue dye for ritual fringes only from a reliable individual, as it is easy to counterfeit it. Rav Huna then came before Rav Yosef to ask if he could rely on her assurance that it was usable for the mitzva. The answer was not available to Rav Yosef.

Later, Ḥanan the tailor happened to meet Rav Huna, and he said to him: From where could poor Rav Yosef have known the answer to this question? Ḥanan continued: There was an incident in which I was involved, as I purchased sky-blue dye from the people of the household, i.e., the wife, of Rabena’a, brother of Rabbi Ḥiyya bar Abba, and I came before Rav Mattana to ask him the same question, and the answer was not available to him either. I then came before Rav Yehuda of Hagronya, who said to me: You have fallen into my hand, i.e., I am the only one who can answer your question. This is what Shmuel says: The wife of a ḥaver is herself considered like a ḥaver, and you may therefore rely on her statement.

The Gemara comments: We learn here that which the Sages taught explicitly in a baraita: The wife of a ḥaver is like a ḥaver; the slave of a ḥaver is like a ḥaver. Furthermore, with regard to a ḥaver that died, his wife and children and members of his household remain in their presumptive status until they are suspected of engaging in inappropriate deeds. And similarly, with regard to a courtyard in which they sell sky-blue dye, it remains in its presumptive status as a place in which kosher sky-blue dye is sold until it is disqualified due to unscrupulous behavior.

The Sages taught: The wife of one who is not careful to keep the particulars of certain halakhot [am ha’aretz], who later marries a ḥaver, and likewise the daughter of an am ha’aretz who marries a ḥaver, and likewise the slave of an am ha’aretz who is sold to a ḥaver, must all accept upon themselves the commitment to observe the matters associated with ḥaver status. But the wife of a ḥaver who later marries an am ha’aretz, and likewise the daughter of a ḥaver who marries an am ha’aretz, and likewise the slave of a ḥaver who was sold to an am ha’aretz, these people need not accept upon themselves the commitment to observe the matters associated with ḥaver status ab initio. This is the statement of Rabbi Meir.

Rabbi Yehuda says: They too must accept upon themselves the commitment to observe the matters associated with ḥaver status ab initio. And similarly, Rabbi Shimon ben Elazar would illustrate this point and say: There was an incident involving a certain woman who married a ḥaver and would tie for him phylacteries on his hand, and she later married a tax collector and would tie for him tax-seals on his hand, which shows that her new husband had a great influence on her level of piety.

§ Rav says: The substances represented by the acronym ḥet, beit, yod, tav are prohibited if they were deposited with a gentile while they were sealed with only one seal. Those represented by the acronym ḥet, beit, peh, gimmel are permitted if they were deposited with a gentile while they were sealed with one seal. The Gemara elaborates: Milk [ḥalav], meat [basar], wine [yayin], and sky-blue dye [tekhelet]