83a middle
The gemoro explains the machlokes of reb yosi and reb shimon with the others, about how many days before sheviis does kelita of harkovas zeroim take place.
After discussing the machlokes and officially paskening like reb yosi. The gemoro randomly brings in "reb nachman omar rabba bar avuha says, acc. To 3 its 3 plus 30, acc to 2 weeks its 2 weeks plus 30." How does this come into our sugya at all, it seems totally out of place. Why is it necessary to say this random din about sheviis?
Avrumi Hersh, London england
A good sign if one is learning in the right way is when his questions are discussed in the Rishonim!
(a) The Tosfos ha'Rosh asks your question and leaves it unanswered.
(b) Rashi explains Rav Nachman to be referring to Tosefes Shevi'is, as you brought, but Tosfos argues that the Halachah (l'Moshe mi'Sinai) of Tosefes Shvi'is is only on grain fields and does not include fruit. This argument is discussed originally in the Rishonim in Maseches Rosh Hashanah. (The Tosfos Rid along with many other Rishonim agree with Tosfos. He says that Rashi "Bilbel at ha'Olam with his Shitah"!)
(c) According to Tosfos, Rav Nachman is not referring to Shemitah at all, but rather to the Isur of Orlah. This Shitah is cited nby Tosfos in Rosh Hashanah (10b), but Tosfos there adds a small addition which he does not mention here. He mentions your question as a proof to his Shitah and says that the Gemara brings Rav Nachman to add that the Machlokes regarding Shvi'is is relevant to Orlah too, and therefore the Halachah is like Rebbi Yosi also in Orlah.
Kol Tuv,
Aharon Steiner