1)

(a)Even though Rebbi Shimon ben Elazar goes after the majority of people in gauging the Shi'urim - even Lekula - he will agree however, that when it comes to Og Melech ha'Bashan's corpse, we can only render all the other entrances Tahor, if there is an entrance the size of Og himself (and not gauge him by the size of other corpses), because it is a matter of through which doorway Og is going to be moved - and it is not the done thing to cut up a corpse.

(b)The minimum size opening that will allow Tum'as Mes to pass through - is a the size of a fist.

(c)The Beraisa which gives the minimum size entrance or outlet (to save all the other rooms) as four Tefachim - is speaking when there are many other outlets of less than four Tefachim, in which case we will assume that the body will be taken through the larger entrance (since four Tefachim is large enough to allow an average corpse to pass through); Rebbi Shimon ben Elazar, who requires the size of Og (for a corpse the size of Og), does not render the other rooms Tahor, unless it is large enough to allow Og's body through, because in that case, where they are going to gave to enlarge one of the entrances anyway, to take the body for burial, and we do not know which one, we have no option but be Metamei them all.

(d)If all the outlets are the same size, or if they are all too small to allow the body to pass through - then all the rooms are Tamei (we shall see more details of this later in Perek ha'Dor).

2)

(a)Rav Yosef is known as Sinai - due to his phenomenal knowledge of Beraisos; the Shi'ur that he gave for raw eggs (for an Eruv) - is two eggs.

(b)

1. 'Mazon' incorporates - anything made of the five species of grain (wheat, barley, rye, oats and spelt).

2. 'Kol ha'Zan' incorporates - anything which satisfies slightly, including any food other than water and salt.

(c)The fruit of Ginusar was special - insofar as, due to its sweetness, however much one ate, one always wanted more.

(d)Ginusar is better-known as - Kineres.

3)

(a)'Shevu'ah she'Lo Ochal Kikar Zu' - implies that he only places a prohibition on his own eating the food. Consequently, since others are permitted to eat it, he may still use it for an Eruv. 'Kikar Zu Alai', on the other hand, includes all kinds of benefit, and this would include using it for an Eruv - according to Rav Huna quoting Rav.

(b)If we understood the Beraisa of 'ha'Noder min ha'Kikar, Me'arvin Lo Bah' literally (to speak about a Neder) - then we would have to say that 'Harei Alai' does not include even an Isur Hana'ah, but is confined to an Isur Achilah (because it is the most common use of food). This clashes with Rav Huna (who maintains that 'Harei Alai' implies an Isur Hannah, and the food may therefore not be used for an Eruv).

4)

(a)This leaves us with a Kashya on Rav Huna - because, if the Reisha of the Beraisa ('ha'Noder min ha'Kikar, Me'arvin Bah') is confined to Shevu'ah, but not to Neder, then why does the Seifa move on to Hekdesh, and not Neder.

(b)Rav Huna explains that the Beraisa follows the opinion of the Rabbanan, whereas he follows that of Rebbi Eliezer.

(c)Hekdesh is categorically forbidden to be used for an Eruv - because all kinds of benefit are prohibited - to everybody.

5)

(a)The second Tana in Rebbi Eliezer holds - that even using a Neder for one's Eruv is permitted, since, in his opinion, one may only make an Eruv when it is for a D'var Mitzvah, and 'Mitzvos La'av Lehanos Nitnu' (Mitzvos are not considered a source of physical pleasure).

(b)It does not matter that he is not able to benefit from the loaf forbidden through a Neder or a Shevu'ah - since others are permitted to benefit from it, as we have already learned a number of times.

(c)According to Beis Shamai - one cannot make an Eruv for a Nazir with wine, or for a Yisrael with Terumah.

(d)They agree however, that one may make an Eruv for a grown-up on Yom Kippur - because, unlike in the previous two cases, the Eruv is fit for use during the day of Erev Yom Kippur (see Ritva).

6)

(a)According to Chananyah, Beis Shamai permit making an Eruv Chatzeros - only if one has moved all the utensils that he intends to use to that spot.

(b)According to Chananyah, the Beraisa 'Erav bi'Shechorim, Lo Yetzei bi'Levanim' etc. is incorrect - since, not having taken his white clothes there, he is not even permitted to carry his black clothes there either (meaning that he is forbidden to go beyond that point at all, since his Eruv is ineffective).

(c)The Beraisa should have read - 'Erav bi'Levanim, ve'Hutzrach bi'Shechorim, Af bi'Levanim Lo Yetzei' (meaning that, since he did not take everything he wanted, he is not permitted to walk beyond that point).

7)

(a)The reason that Sumchus agrees with the Rabbanan, who permit a Nazir to use wine for his Eruv (despite the fact that he forbids a Yisrael to use Terumah) - is because a Nazir is able to nullify his Nezirus, in which case the wine will be permitted to him (a form of 'Migu')

(b)Nullifying his Terumah however, will not help him - since then it will become Tevel, which remains forbidden to him.

(c)When the Gemara asks why it is not possible to separate Ma'asros using other produce that he has at home - it is speaking about doing this during Bein Hashemashos, which is permitted, according to Rebbi, as we shall see later in the Sugya.

(d)The reason that he cannot do this - is because it is forbidden to take Ma'aser 'she'Lo min ha'Mukaf' (from produce that is not next to the produce that is being rectified).

8)

(a)Sumchus forbids using Terumah for an Eruv - because he does not hold like Rebbi, who permits certain Shevusin (Isurim de'Rabbanan) to be transgressed during the period of Bein Hashemashos. In Sumchus' opinion, there is no Heter to separate Ma'asros during Bein Hashemashos; therefore one cannot use Terumah for the Eruv of a Yisrael.

(b)The author of the Beraisa 'Yesh she'Amru, ha'Kol Lefi Mah she'Hu Adam ... u've'Mazon Shtei Se'udos le'Eruv', must be Sumchus - who permits making an Eruv for someone who is permitted to eat it exclusively (which is why he forbids making an Eruv with Terumah for a Yisrael), and this is precisely what the Beraisa says.

(c)The Gemara thinks the Mishnah in Kelim goes Lechumra after the individual who made the Eruv - even as regards a person with a large appetite, who will require an Eruv to suit his appetite, and not that of most people. If that is so, then the Mishnah will not conform with Rebbi Shimon ben Elazar, who is lenient in such a case, and says 'Ra'avsan bi'Se'udah Benonis shel Kol Adam'.

(d)The Gemara concludes that the author of the Mishnah can in fact be Rebbi Shimon ban Elazar- and when the Beraisa says 'ha'Kol Lefi Mah she'Hu Adam', it is referring to a sick person or an elderly one (Lekula), but not to a person with an appetite. There, the Tana will agree that 'Batlah Da'ato Etzel Kol Adam'.

9)

(a)It is possible to place an Eruv in a Beis ha'Peras for a Kohen - firstly, because it is possible for the Kohen to pass through it by blowing away all the bones in his path (by doing so, he will see all the small bones and be able to avoid them - the large ones he will see and avoid anyway); and secondly, because a Beis ha'Peras that has been well-trodden is Tahor (since the small bones will be ground to less than size of a barley).

10)

(a)Rebbi Yehudah permits placing the Eruv of a Kohen even in a grave-yard - because he holds like Rebbi Yehudah b'Rebbi Yossi, who says 'Ohel Zaruk Sh'mei Ohel' (a moving Ohel has the Din of an Ohel). Consequently, it is possible for a Kohen to enter a Beis-ha'Kevaros in a large box or carriage, without becoming Tamei.

(b)Rebbi holds 'Ohel Zaruk Lo Shmei Ohel' - Consequently, even if the Kohen entered the Beis ha'Kevaros in a carriage, this will not prevent him from becoming Tamei.

(c)The carriage over which they arguing - must at least be able to hold forty Sa'ah (of liquid, or sixty Sa'ah of solid); otherwise, everyone will agree that it will transmit Tum'ah to whoever is sitting inside it.

(d)Both the Rabbanan and Rebbi Yehudah require that one should be able to eat the Eruv at the time when it is placed - like Sumchus (See Tosfos in the Mishnah - 27a DH 'Mipnei', who disagrees with this).