1)

(a)If the threshold referred to by the Tana of our Mishnah is that of a Reshus ha'Yachid (and he permits rolling the Sefer from the Reshus ha'Rabim) then the author of the Mishnah must be Rebbi Shimon - who says that Chazal did not issue any decrees (i.e. waived all Isurim d'Rabanan in face of Kisvei Kodesh. Consequently, even if the Sefer landed in the Reshus ha'Rabim, he will be permitted to retrieve it, since, due to the fact that he still holding the other end, there is no Isur d'Oraysa, only an Isur d'Rabanan.

(b)Having just established the Reisha like Rebbi Shimon, then how can the Mishnah go on to say that Rebbi Yehudah only permits retrieving the scroll as long as it has not landed on the ground, and Rebbi Shimon permits it even if it has? This would mean that the Reisha and the Seifa are Rebbi Shimon, and the Metzi'asa, Rebbi Yehudah - which seems rather odd!?

(c)Rabah establishes our Mishnah even according to Rebbi Yehudah, who is generally strict even by Kisvei Kodesh - but here even he will concede that one needs to make a concession, due to the fact that the Sefer is lying in the street, and there is a strong suspicion that people will tread on it (a more serious violation than a Sefer which merely lies on the ground). Therefore he too will agree that we waive the Isur d'Rabanan, and permit him to roll the Sefer back .

(d)If the author of the Reisha is Rebbi Yehudah, and his reason is as Rabah describes, then why would the Beraisa differentiate between less than four Amos and more (what is the difference between bringing it from the Reshus ha'Rabim to the Reshus ha'Yachid, and moving it four Amos in the Reshus ha'Rabim)!?

2)

(a)According to Abaye (who establishes the Beraisa by an Iskupas Karmelis) - the Beraisa restricts the Heter of rolling the Sefer back, to less than four Amos, because, even if the Sefer would fall right out of his hands, and he would go and retrieve it, he would only transgress an Isur d'Rabanan (i.e. from the street to the Iskupah); whereas, if it rolled more than four Amos into the street, he would not be allowed to roll it back, since, if if it were to fall right out of his hands, and he would go and retrieve it, he would be performing an Isur d'Oraysa (by carrying it four Amos in the street).

(b)Since the author of the Mishnah is Rebbi Yehudah, why do we not forbid him to roll the Sefer even when it has rolled less than four Amos - for fear that it might fall, and he goes to retrieve it, and carries it back into the Reshus ha'Yachid via the threshold.

(c)Establishing the Mishnah by a long threshold will solve this problem - because we assume that, by the time he arrives at the end of the long Karmelis he will remember, and stop to rest (in the Karmelis).

(d)Alternatively, we establish the Beraisa by an ordinary size Karmelis, and we are not worried that he will carry the Sefer from one Reshus to the other, because most people tend to look at the Sefer and study it as they walk along, in which case, he will probably stop on the threshold.

3)

(a)Even if he does carry the scroll directly from the Reshus ha'Rabim straight through the Karmelis to the Reshus ha'Yachid without stopping - he will not be Chayav, explains the Gemara, because the author of our Mishnah (as well as of the Beraisa), is Ben Azai, who holds 'Mehalech k'Omed Dami', in which case, he will be Patur the moment he steps on to the threshold.

(b)Neither are we afraid that he may throw the Sefer from the Reshus ha'Rabim to the Reshus ha'Yachid - because it is forbidden to throw Sefarim.

(c)A Sofer should leave Sifrei Kodesh covered to protect the script, and not turned over with the script facing the ground.

(d)But that is only if he has the choice - someone whose Sefer falls on Shabbos and who is not able to cover it with anything, should choose the better of two evils, and turn it over on to its script - to protect it - than leave it lying exposed to the elements.

4)

(a)When the Mishnah speaks about turning a fallen Sefer that stops within ten of the ground, on its face - it is referring to a Sefer that stopped on a sloping wall, not in mid-air, as we originally thought.

(b)In fact, before Rebbi Yehudah in the Seifa, we need to add a few words. This is how the Mishnah reads: 'Bameh Devarim Amurim, b'Kosel Meshupeh, Aval b'Kosel she'Einah Meshupeh, Lema'aleh mi'Sheloshah, Golelo Etzlo, Lematah mi'Sheloshah, Hofcho Al ha'K'sav. Rebbi Yehudah Omer, Afilu Eino Mesulak Min ha'Aretz Ela Ki'melo ha'Chut, Golelo Etzlo'.

5)

(a)The Tana Kama holds that if the Sefer is within three Tefachim of the ground, it is forbidden to roll it back - even if it did not land on anything. According to Rebbi Yehudah, as long as the Sefer did not yet land on anything, he is permitted to roll it back.

(b)Rava says that (according to the Rabanan of Rebbi Akiva, who do not hold of 'Kelutah k'Mi she'Hunchah Dami') an object that is within three Tefachim of the ground - must come to rest on something in order to be Chayav for throwing.

(c)Consequently, in order that Rava's statement should be unanimous - we establish only one opinion in our Mishnah (not like we just learnt in a.); namely, that of Rebbi Yehudah, who holds that when the Sefer does not land on a wall, he is permitted to roll it back even when it is within three Tefachim of the ground.

6)

(a)The ledge in front of the window, from which the Mishnah permits placing things and taking from it - is four Tefachim wide and ten Tefachim high.

(b)We are not afraid that the vessels may fall, and the owner will go and retrieve them - because this Din is confined to breakable vessels.

7)

(a)One may not use a ledge which is less than four Tefachim, even though it is a Makom Petur - because using such a ledge on a regular basis will result in many vessels falling and breaking, and this looks as if the owner is deliberately throwing things into the street. And whenever Chazal permit using a Makom Petur, it is always 'Lekatef Alav' (resting things on it - casually), but never on a regular basis.

(b)When the Beraisa restricts the use of the top ledge, to the part which is in front of the window only - it is speaking about a ledge which itself, does not protrude four Tefachim from the wall, and which is therefore forbidden to use (as we just explained). However, the part that is in front of the window, which together with the window, does total four Tefachim, may be used.

(c)The lower-ledge (which is more than four Tefachim wide) may be used - in spite of the fear that, due to the upper-ledge, which makes it difficult to get to, things will easily fall off.

8)

(a)'Omed Adam bi'Reshus ha'Yachid u'Metaltel bi'Reshus ha'Rabim, bi'Reshus ha'Rabim, u'Metaltel bi'Reshus ha'Yachid - u'Vilevad she'Lo Yotzi Chutz me'Arba Amos'.

(b)In the previous case, one has not transferred from one Reshus to another (as the Mishnah itself has clearly stated); whereas if one urinates or spits from one Reshus to the other, he has.

(c)Rebbi Yehudah adds - that once the spittle has come loose in one's mouth, one may not walk with it four Amos in the street, but is obligated to spit it out. This is because, once the spittle comes loose, it stands to be emitted, and is considered a burden for which one Chayav on Shabbos.

9)

(a)Rebbi Meir prohibits standing in one Reshus and carrying in the other - for fear that he may bring the object to him.

(b)Rav Chinena bar Shalmayah believed the text in our Mishnah to be 'Lo Ya'amod Adam' (like Rebbi Meir) - since the Seifa of the Mishnah (on Daf 101a) goes like Rebbi Meir.

10)

(a)Rava says 'ha'Ma'avir Chefetz mi'Techilas Arba l'Sof Arba, v'He'eviro Derech Alav, Chayav'.