A Gezeirah for Hekter Chalavim V’Eivarim?

Rabban Gamliel, in the Mishnah, includes the hekter chalavim v’eivarim (the burning of the fats and the limbs from the day’s sacrifices) together with k’riat shma as examples of mitzvot that apply the entire night. The implication would seem to be that, as with shma, the chakhamim instituted a g’zeirah that the hekter should be done before chatzot. This is indeed the opinion of the Rambam (Hilkhot Ma’aseh HaKorbanot 4:2, Hilkhot T’midin U’Musafin 1:6). Rashi (s.v. k’dei), however, disagrees, and believes only k’riat shma was so limited; the hekter is mentioned only to show that nighttime mitzvoth apply all night on a biblical level.

The Lubavitcher Rebbe, zatzal (Chiddushim U’Biurim, I, 1) suggests that Rashi felt a g’zeirah would not be applied in that case due to a principle articulated by the Taz in many places, that the Rabbis cannot prohibit something that is explicitly permitted in the text of the Torah. Since, in the context of hekter chalavim v’eivarim, the Torah says explicitly that the process can take place the entire night. Thus, a g’zeirah would not be instituted in this case.

The Rambam, however, who does believe a g’zeirah to have been applied, must understand differently. The consumption of the remnants of the sacrifices involves two aspects: a) a positive commandment, encompassing several conditions, to consume the sacrificial elements; and b), a preventative measure to forestall violating the prohibition of leaving any remnants over to the next day (notar). Perhaps, then, the Rambam’s version of the principle is different that that of the Taz, and he believes that the Rabbis did limit areas explicitly permitted by the Torah, as long as they don’t infringe on a mitzvah. Thus, the first aspect, which represents an active mitzvah, is not limited by the Rabbis, as that was meant to be performed during the daytime in any event. The second element, which they did limit, is not an active mitzvah but rather a method to prevent a prohibition. (See also Resp. Kol Aryeh, Orach Chaim, 29).