Continuing the series I started on Rav Wahrman's Oros Shabbos, this week I want to share something a little more technical from later in the sefer (siman 31). Aside from novel sevaras, Rav Wahrman also does an impressive job of collecting bekiyus. Watch what he does in putting together a Kapos Temarim with a teshuvah of the MahR"Y Asad:
We know that the source for melachos of Shabbos is the Mishkan (either building, or the work done therein -- different views in Rishonim). With respect to moving objects on Shabbos, there are two potential melacha elements: hotza'ah, carrying from one domain to another, and ma'avir, carrying an object 4 amos in a public domain. The gemara (Shabbos 96b) explains exactly where the melacha of hotza'ah occurred in the Mishkan. However, the gemara findd no source in the Mishkan for ma'avir and concludes it is a halacha l'Moshe m'Sinai.
The fact that these two elements have two different sources leads to a number of interesting differences between them:
1. The Kapos Temarim (Sukkah 43) writes that the ptur of melacha she'aina tzericha l'gufa (i.e. there is usually no issur d'oraysa if a melacha is done for some other purpose other than it was used for in the Mishkan) does not apply to the issur of ma'avir. The ptur of melacha she'aina tzericha l'gufa is derived from the fact that the Torah says only meleches machsheves, melachos done with intention, as they were done in the Mishkan, are chayav on Shabbos. Since the issur of ma'avir is not patterened after the Mishkan, but is rather a separate halacha l'Moshe m'Sinai, it does not need to conform to any Mishkan-use purpose to be chayav. (This is a tremendous chiddush, which R' Wahrman notes can be disputed from other sources in Rishonim.)
2. The definition of reshus ha'rabim, a public domain, for the purposes of hotz'ah is also based on the melacha's source. The Mishkan, where the paradigmatic melacha of hotz'ah took place, was the central point of Bnei Yisrael's camp of 600,000 people; therefore, a reshus ha'rabim is defined as an area where there are 600,000 people (there are lots of technical details to this point that are relevant for hil eiruvin, but lets keep it simple for now). What about ma'avir? When we speak about the issur of carrying an object 4 amos in a public domain, what do we mean by "public domain"? MahR"Y Asad writes that since ma'avir is a halacha l'Moshe m'Sinai and not derived from the Mishkan, the standard of 600,000 goes out the window and does not apply.
Using this foundation, we can now solve a difficulty raised by Tosfos. Chazal made a gezeirah not to perform the mitzvos of lulav, shofar, and megillah on Shabbos lest a person who does not know how to do the mitzvah carry the lulav, the shofar, or the megillah to an expert to teach him what to do. "Amar Rabbah: Gezeirah shema ya'avirenu 4 amos b'reshus ha'rabim" -- Rabbah taught that the gezeirah is in place lest a person carry 4 amos in a public domain.
Why, asks Tosfos, does Rabbah focus only on the potential issur of carrying 4 amos in a public domain? Wouldn't the person who carries in the street also violate the issur of hotza'ah, of taking an object from the public domain of the street into the private domain of the expert who is going to teach him how to do the mitzvah? Why does Rabbah not use this as the basis for the gezeirah?
Putting together what we learned from the Kapos Temarim and the MahaR"Y Asad, we can resolve Tos.' question. The issur of hotza'ah is learned from the Mishkan and applies only where the public domain encompasses 600,000 people; the issur of ma'avir is a seperate halacha l'Moshe m'Sinai with its own parameters that applies to any public space. Chazal may not have been motivated to create a gezeirah for the relatively rare cases of domains populated by 600,000 people. They were, however, still concerned about carrying in public areas using the broader definition of the term.