On RH 31a, R' Avkiva says that Mizmor Shir LeYom Hashabbos refers to Yom Shekulo Shabbos i.e. in the future. R' Nechemya asks that this is not consistent with the other days, and he says that it refers to the Shabbos of Maase Bereishis. The Gemoro then says that they argue about the statement of Rav Ketina; Rashi explains that R' Nechemya doesn't hold of Rav Ketina, so he can't say refers to the 1000 years of the future.
My questions is why is the Gemoro forced to say that they argue about Rav Ketina? Maybe R' Nechemya does hold of Rav Ketina, but he prefers his pshat as he in fact said to R' Akiva, that his pshat is more consistent, since all days refer to the past!
Kol Tuv
Meir Eliezer Bergman
Manchester UK
Your question is asked by the Turei Even and the Yom Teru'ah, two of the primary commentators on the Maseches!
The Turei Even answers that the Gemara is not certain that the reason Rebbi Nechemyah presenting in the Beraisa represents his true reasoning. Often we find that a Tana will present an argument to explain why he argues with another Tana, when he himself does not accept such an argument as valid. (I found examples of this in Tosfos Yoma 56b DH Rebbi Yehudah -MK.)
The Turei Even proves that his contention is correct from the fact that the Gemara feels it necessary to find a Tana who holds like Abaye. If Rebbi Nechemyah clearly supports Abaye, why is it necessary to find another Tana who supports him? It must be that the Gemara is not certain whether it can be proven that Rebbi Nechemyah holds like Abaye, or not.
Best regards,
Mordecai Kornfeld