QUESTION: Rav rules that in the case of a wall between two Chatzeros that fell down, one may not carry in either Chatzer more than four Amos, just as one may not carry in a Karmelis.

Why is one prohibited to carry in either Chatzer? Rav rules like Rebbi Shimon (90a) that all adjoining Chatzeros are considered one Reshus and thus one may carry utensils from one Chatzer to another, as long as those utensils were in the Chatzer before Shabbos began. Why, then, does he prohibit one to carry in the Chatzer when a wall between the two Chatzeros fell down?

(a) RASHI answers that Rebbi Shimon's ruling that one may carry from one Chatzer to an adjacent Chatzer applies only when the residents of the Chatzeros did not make individual Eruvin to permit carrying in their respective Chatzeros. In the case of Rav, each Chatzer made its own Eruv which permits the residents of each Chatzer to carry items from their homes into the Chatzer. Rav maintains that there is a decree that prohibits carrying anything from one Chatzer to another, including items that were in the Chatzer when Shabbos began, lest one carry items that were in the house when Shabbos began (such items may not be carried from one Chatzer to another). Accordingly, Rav is consistent with his opinion earlier (91a) that Rebbi Shimon does not permit one to carry from one Chatzer to another when the houses in the Chatzer made an Eruv, which permits items to be carried from the houses into the Chatzer.

(b) TOSFOS (DH Ein) explains that Rav's ruling applies whether or not the residents of the Chatzeros made Eruvei Chatzeros for themselves. When Rav says that one may not carry in the Chatzer more than four Amos, he refers only to utensils that were originally in the house and were moved to the Chatzer on Shabbos. Although normally one is permitted to carry such items throughout the Chatzer to which the house opens (see Insights to Eruvin 91:1), in this case the Chatzer to which the house opens is Parutz b'Milu'o, open on one entire side (the side of the fallen wall), to a Chatzer in which these utensils may not be carried. This prohibits carrying them in the first Chatzer as well.

However, utensils which were in the first Chatzer at the onset of Shabbos may be carried throughout that Chatzer and its adjacent Chatzer, because of Rebbi Shimon's ruling that all Chatzeros are like one. With regard to those utensils, the adjacent Chatzer is not a forbidden area, and it does not forbid carrying in the first Chatzer.

It is evident from the words of Tosfos that when a Chatzer is Parutz b'Milu'o to a place in which one is selectively prohibited to carry (that is, certain forms of carrying are prohibited, while other forms are permitted), it is considered to be Parutz b'Milu'o l'Makom ha'Asur Lo (open on an entire side to a place in which one may not carry) for a certain type of carrying, while other types of carrying remain permitted in both areas.

Rashi argues with this principle of Tosfos in a number of places in the Maseches. He does not agree that a Chatzer can be considered open to an area in which one is forbidden to carry with regard to certain utensils or certain forms of carrying, while it is considered open to an area in which one is permitted to carry with regard to other utensils or other forms of carrying. (See Rashi to 42a, regarding the case of the Nochrim who built Mechitzos around a Jew on Shabbos. Rashi there says that an area cannot be called "Parutz b'Milu'o l'Makom ha'Asur Lo" unless it is open to a place where one cannot carry anything. If one is permitted to carry some types of items to that area, it is not called a "Makom ha'Asur Lo" at all.) In the case of the Gemara here, as far as the utensils of the Chatzer are concerned, the other Chatzer is a Makom ha'Mutar Lo, and therefore it cannot be considered a Makom ha'Asur Lo at all, even for the utensils of the house.

TOSFOS (42a, DH u'Metaltel; 42b, DH Lo; 89a, DH Rav), on the other hand, maintains that even if the adjacent area has a partial use, then for those items that one is permitted to carry there it is considered a Makom ha'Mutar Lo, and for those items that one is not permitted to carry there it is considered a Makom ha'Asur Lo.

(See the Gadol of Minsk's YISRON HA'OR printed at the end of the Mishnayos, Eruvin 9:1, and see also Rav Chaim Dickman's notes to Tosfos Rabeinu Peretz.)