Avodah Zarah Daf 40 עבודה זרח דַף 40

The Mishnah on the previous Daf taught that טרית שאינה טרופה – [a type of small fish] which is not minced is permitted to eat. A Baraisa explains: כל שראש ושדרה ניכר – all whose head and spine are recognizable as kosher fish. Rav Huna says this means עד שתהא ראש ושדרה ניכר – it is not permitted unless both the head and spine are recognizable, but Rav Nachman says it is sufficient if either the head or spine is recognizable. Both are challenged by a Mishnah which states that the signs for kosher fish are fins and scales (implying there are no other signs), and the Gemara answers that this refers to particular species ("ארא" and "פלמודא") whose heads are similar to those of non-kosher fish. עולא said this machlokes is only לטבל בצירן – to dip into their brine (whether the possible non-kosher fish would Biblically nullified), but בגופן – regarding eating [the fish] themselves, all agree that both the head and spine must be discernible. Rav Pappa concluded: הלכתא עד שיהא ראש ושדרה ניכר של כל אחת ואחת – the halachah is that טרית cannot be eaten unless the head and spine of each and every one are recognizable.

Rav said: קירבי דגים ועוברן אין נקחין אלא מן המומחה – the innards of fish and their roe may only be purchased from an expert in identifying kosher species. Ulla objected that roe should not require identification, because a Baraisa states דג טמא משריץ – a non-kosher fish bears live young, and only a kosher fish produces eggs!? Rebbe Dostai of Biri said to remove “roe” from Rav’s statement, but Rebbe Zeira answered that both types of fish produce eggs, but the non-kosher fish hatch inside the mother’s body. The Gemara asks that kosher eggs can be identified based on their shape, or the location of the yolk in the egg, and Rava explains: כשנימוחו – the case is where [the roe] is dissolved and cannot be examined and therefore may only be purchased from an expert. If there is no expert, Rav Yehudah says it may be purchased from a seller who says: אני מלחתים – “I salted [the fish] myself (and saw they were kosher, and these innards are from them).” Rav Nachman says he must actually show the fish from which he took the innards.

The third Perek begins: כל הצלמים אסורין – all human images are prohibited in benefit, מפני שהן נעבדין פעם אחת בשנה – because they are worshipped once a year. This is Rebbe Meir’s opinion, but the Chochomim say: אינו אסור אלא כל שיש בידו מקל או צפור או כדור – [an image] is not prohibited unless it has in its hand a staff, a bird, or a sphere. The items in their hands are intended to depict their power over the world, and such images were more likely worshipped. Rabban Shimon ben Gamliel prohibits any image which has anything in its hand. The Rabbonon agree that any image worshipped even once a year is prohibited. Rebbe Yochanan explains that in Rebbe Meir’s location, they would worship all the צלמים once a year; therefore, Rebbe Meir, דחייש למיעוטא – who is concerned for a minority, גזר שאר מקומות אטו אותו מקום – decreed to prohibit all locations (whose practices are unknown) based on his location, because of the (remote) possibility that those locations are like his own. The Rabbonon are not concerned about מיעוטא and so did not prohibit locations which are not known to worship all צלמים once a year.