Shiur Supplement #22 Daf 22a
A. Meitiv R. Yitzchak Nafcha [lines 5-9] Backround: The Torah (Bereishit 32:25-33) records the story of the fight that took place between Ya'akov and a mysterious assailant (according to some- the protecting angel of Eisav). The assailant was overpowered by Ya'akov, and in order to break loose, he injured his thigh (by applying pressure to the nervus ischiadicus or gid ha-nashe). Although this was unsuccessful and he was forced to bless Ya'akov before he could be set free, nevertheless, Ya'akov limped afterwards as a result of his injury. Thus, in commemoration of the assailant's attack, Bnei Yisrael are forbidden to consume the gid ha-nashe of any animals they eat.
The Torah formulates the prohibition against eating the gid ha-nashe as "lo yokhlu." In keeping with the rule of R. Abahu, this should necessarily imply an issur hana'a (prohibition against benefit); however it is PERMITTED to benefit from the gid ha-nashe (eg. By giving it as a present to a non-Jew) and thus, the validity of R. Abahu's rule comes into question.
B. Hanicha le-man de-amar yesh be-gidin [lines 10-12] Background: The gemara in Chullin (daf 100b) records an argument between R. Yehuda and R. Shimon. According to R. Yehuda, one who eats the gid ha-nashe of a non-kosher animal (eg. A horse) receives two sets of malkot (lashes). According to R. Shimon, he receives no punishment whatsoever. The argument is based on the following disagreement: R. Yehuda views the gid ha-nashe as meat, whereas R. Shimon does not. In the language of the gemara - according to R. Yehuda - YESH be-gidin be-notein ta'am (the gid gives taste when cooked with something); according to R. Shimon - EIN be-gidin be-notein ta'am (the gid does NOT give off taste).
The gid ha-nashe can only be considered to have been permitted be-hana'a as part of the neveila if it is considered like meat of the neveila (ie. If YESH be-gidin be-notein ta'am).