R. Yosi uses b'makhelos to teach halacha (The Berachah is according to the number of people). When the gemara asks what R. Akiva uses it for it cites R. Meir's aggadic insight that "even fetuses sang Shirah at Keri'as Yam Suf." We should be looking for an alternate HALACHIC drush R. Akiva uses b'mkhelos for. Since when is it possible to say a word in a pasuk is used for something aggaddic to counter another opinion using it to teach an halacha?
Yaakov Astor, Monsey, NY
Thank you for your question. I think that the answer lies in understanding the basic meaning of the verse.
The verse does not appear in a Halachic section, but rather in a Perek of Tehillim (68) which discusses the history of B'nei Yisroel in the days of Yetzi'as Mitzrayim. It relates that B'nei Yisroel then gathered to bless Hash-m. There is no need to repeat the story, which appears in the Chumash, unless there are additions we were unaware of until now. Rebbi Akiva explains the new revelation of the Pasuk shows us that even a fetus sang Shirah. Rebbi Yosi on the other hand feels that the word "b'Makhelos" is nonetheless extra. He thus explains that the word "b'Makhelos" shows us that the size of the congregation had an influence of the format of the Shirah. If this was the case, we can learn from here that we should also change the format of a Berachah based on the size of the congregation. Rebbi Akiva does not feel that this word is extra.
See also Nazir 2b, where the Tana'im argue regarding the Halachah of whether a Bechor can be used for Hatfasah for a Neder, based on the verse "la'Hashem." The Gemara concludes that although the Torah uses the term "la'Hashem" by a Nazir, it is not meant to teach that Hatfasah can be made from a Neder. Rather, it teaches that the only Nazir whose intentions are fully l'Shem Shamayim is one who makes himself a Nazir in order to avoid becoming arrogant (like the story of the Nazir of Shimon ha'Tzadik).
It seems that, at least under certain circumstances, it is acceptable to "use up" a verse for a Drush such that it is no longer available for Halachic exegesis.
(Please accept our apologies for the delay in getting back to you on this. Due to the pressures of organizing our Grand Siyum and Pesach vacation, the Kollel fell behind in keeping up with our email questions. We are now back on track, and you should receive prompt answers to any future questions, G-d willing.)