(Beraisa - Others): The status of the threshold alternates - when the door is open, it is like inside [the house, Reshus ha'Yachid];

When the door is closed, it is like outside (Reshus ha'Rabim).

Question: Is this even if there is no Lechi? (A Lechi (vertical post) helps permit carrying in an open Mavuy, either because it demarcates the end of the Mavuy, or because it is considered a Mechitzah.)

But Rav taught, to permit carrying in the opening (i.e. even with the thickness of a Lechi which ends at the end] of the Mavuy, a second Lechi is needed (totally outside the Mavuy, for a Lechi only permits carrying from its inner end; the threshold is like the opening of a Mavuy!)

Suggestion: The threshold is less than four by four.

Objection: Rav taught, even if the opening is less than four by four, a second Lechi is needed!

Answer #1 (Rav): Others discuss the threshold of a Mavuy [permitted by a Korah, a beam over the entrance], only the inner half is covered [by the Korah] - when the door is open, it is like inside [Rav permits carrying under the Korah];

When the door is closed, it is like outside (a Korah does not permit an area less than four by four).

Answer #2 (Rav Ashi): Really, it discusses the threshold of a house - the case is, there are two Koros less than three Tefachim apart, and the door is in the middle;

When the door is open, it is like inside - Lavud joins the Koros, so they are like one roof that is four wide, Pi Tikra Yored v'Sosem (the outer edge is considered a Mechitzah, as if it descends to the floor).

When the door is closed, it is like outside - we cannot join the Koros through Lavud.

(Beraisa): If the threshold is 10 tall and four wide, it is a Reshus [ha'Yachid] unto itself.

This supports R. Yitzchak bar Avodimi:

(R. Yitzchak bar Avodimi): R. Meir says, whenever there are two Reshuyos [ha'Yachid] by each other, such as a pillar 10 tall and four wide standing in Reshus ha'Yachid, it is forbidden to adjust a load on it;

This is a decree, lest one do so on a mound (10 tall and four wide, which is Reshus ha'Yachid) in Reshus ha'Rabim.

(Mishnah): The following are forbidden from shortly (a half-hour) before the time of Minchah, until praying:

To begin a haircut from a barber, to enter the bathhouse or a tannery, to eat, to judge;

If one began, he need not stop.

We stop to say Shma, but not for prayer.

(Gemara) Question: Before which Minchah are these forbidden?

Answer #1: They are forbidden before Minchah Gedolah (which starts half an hour after noon).

Objection: Why should these be forbidden - there is plenty of time to finish them and pray afterwards!

Answer #2: They are forbidden before Minchah Ketanah (which starts three and a half hours after noon).

.Suggestion: The Mishnah refutes R. Yehoshua ben Levi!

(R. Yehoshua ben Levi): It is forbidden to eat anything once the time of Minchah arrives.

Rejection (and Defense of Answer #1): Really, they are forbidden before Minchah Gedolah;

Answer #1 (to Objection (d)): (The Mishnah discusses elaborate activities which could last the entire afternoon) - it refers to the haircut of Ben El'asa (like that of the Kohen Gadol, in which each hair reaches to the next), and to a big tannery (with many skins, at the beginning of their tanning), and to the full works in the bathhouse (shampoo, rinsing in hot and cold water, and a steambath), and eating a big meal (e.g. at a wedding), and to the beginning of judgment.

Answer #2 (to Objection (d) - Rav Acha bar Yakov): The Mishnah discusses a normal haircut - Chachamim decreed not to start before prayer, lest the scissors break;

A mere steambath is forbidden, perhaps he will grow faint and be unable to pray;

One may not peruse his skins in a tannery (even in the middle of tanning), lest he see that he will suffer a loss, and will be upset and unable to pray;

One may not begin even a small meal, lest it get drawn out;

One may not even finish judgment before praying, lest he will see a reason to change the verdict [and will start to judge anew].

Question: What is considered the beginning of a haircut (after which it is permitted to continue)?

Answer (R. Avin): It is from when the barber puts the smock on the customer's knees (Aruch - from when the customer puts his turban on his knees).

Question: What is considered the beginning of a bath?

Answer: It is from when he removes his cloak (Rashi - his outermost garment; Rambam - his undergarment).

Question: What is considered the beginning of entering the tannery?

Answer: It is from when he rolls up his sleeves.

Question: What is considered the beginning of eating?

Answer #1 (Rav): It is from when he washes his hands.

Answer #2 (R. Chanina): It is from when he unties his belt.

Resolution: R. Chanina discusses the law in Bavel (where people used to gird themselves tightly, one must untie his belt before eating), Rav discusses the law in Eretz Yisrael.

(Abaye - many change this to say Ze'iri, for Abaye lived in Bavel): For our colleagues in Bavel, according to the opinion that Tefilas Ma'ariv is optional (Tosfos - i.e. one need not strive to fulfill it as much as other Mitzvos), if one untied his belt [to eat before praying Ma'ariv, even though this is forbidden l'Chatchilah], since it would be a toil to tie it again, he may eat before praying.

Inference: The opinion that Ma'ariv is obligatory requires him to retie it and pray Ma'ariv before eating.

Question: But all agree that Minchah is obligatory, and the Mishnah permits one to finish eating if he began, and R. Chanina taught that this is once he untied the belt!

Answer #1: We are more stringent regarding Ma'ariv for it is common for a person to get drunk at night, therefore there is more danger that if he eats first he will miss praying - there is less concern for this regarding Minchah.

Answer #2: We are more lenient regarding Minchah because the time to pray is limited, people fear missing it, they are not prone to delay praying - since one may pray Ma'ariv the entire night, people do not fear missing it, and they are prone to delay it.