Explanation: Rashi explains that this refers to a pipe into which water is poured from the river with a pitcher. This moves the water around the field.

Explanation (cont.): This does not mean that the pipe is called an Arisa, as the Targum for "Ye'orim" is Arisai. Furthermore, the Gemara in Bava Kama (50b) discusses an ox that fell into an Arisa (not a pipe). The Gemara there implies that it was ten Tefachim deep.

Opinion #1: The Bahag explains that it is permitted to immerse one's hands in a vessel, as this is called Netilah.

Proof: He proves this from the Gemara in Zevachim (21a) that asks, can one do Kidush Yadayim v'Raglayim in the Kiyor? The Torah says, "from it" implying not in it. This implies that the question stems from the fact that the Torah says, "from it." (Since there is no such Pasuk regarding Netilas Yadayim) One should therefore be allowed to even do Netilas Yadayim in a vessel.

Question: His explanation has a difficulty. Our Gemara says one cannot take from this water pipe because the water did not come from the power of a person. This implies that a person's power of pouring the water (onto hands) is required for Netilas Yadayim!

Answer: It is possible to answer that we require Netilah from a vessel, whether he immerses his hands in the vessel or he pours water on them from the vessel. However, here his hands are outside of the vessel, and the power of the vessel is no longer present when the water spill onto his hands from the pipe. Therefore, it is not considered Netilah from a vessel nor is it immersion, as the water is Mayim She'uvin (invalid for Mikvah as it was in a vessel).

Implied Question: The Gemara says that the water is not coming from the power of a person. (How does this fit with what we just said that it can also be from a vessel?)

Answer #1: It doesn't mean specifically from the power of a person, but rather it means that since it is not from the power of a vessel it is invalid, as we require Netilah from a vessel (i.e. either in a vessel or from a vessel, as stated above).

Answer #2: Alternatively, this is because the Mishnah in Yadayim (1:5) says that everyone is valid for pouring water, even a deaf mute or insane person or a minor. He can put a barrel between his legs and do Netilah, and put a barrel on its side and do Netilah. A monkey can pour water on his hands. Rebbi Yosi says both cases are invalid, meaning both the monkey and the barrel on its side and the water pours on its own (due to the angle) over his hands. This is because Rebbi Yosi requires a person's power, while the Tana Kama only requires the power of the vessel.

Answer (cont.): This would mean that our Gemara that says the power of the person is required is according to Rebbi Yosi.

Observation: However, the Bahag can only hold like the Rabbanan.

Opinion #2: One must be stringent (unlike the Bahag), since our Gemara is according to the opinion of Rebbi Yosi.

Opinion: If a person washes one of his hands and rubs it with his other hand, he must wash his hand again.

Proof: This is as the Mishnah states in Yadayim (2:3) that a person who washes one hand and rubs his other hand has caused his first hand to become impure.

Opinion: If he soaks his bread in water or washes dishes with water he has caused the water to become unfit for Netilah. If he washes his hands with the water they can still be used for Netilah, as this is stated in the Mishnah in Yadayim.

Opinion (cont.): One must pour water on his hands three times: Once to ensure any plaster or thing that is a Chatzitzah is removed, a second time to purify his hands, and a third time to purify the water on his hands. It is apparent from many places in Yadayim that one requires a first and second pouring.

Opinion (cont.): However, if he pours a lot of water equivalent to the amount of a Revi'is on his hands, they are pure (with only one pouring). This is as the Mishnah states in Yadayim (2:1) that if he purified one hand with one pouring, he has purified it. If he purifies two hands from one pouring, Rebbi Meir says the hands are impure until he washes with water that is (i.e. amounts to) a Revi'is. This means that even if the water comes from leftover water purifying other hands it is valid. A Revi'is is not required when one washes in two washings.

Opinion (cont.): Where there is only one pouring, a Revi'is is required. However, when a person washes only one hand he does not require a Revi'is when it comes from water that purified other hands. Rather, he just needs that pouring to be the amount of two regular pourings.

Implied Question: This is despite the fact that regarding immersing his entire body it would not be valid for two reasons. One is because we hold Nitzuk Aino Chibur (a poured stream from entity to another is not considered to connect those two entities), and the other is because we hold that one requires a hole the size of a tube put in the mouth of a leather jug (the size of two fingers) in order to consider Mikvaos connected. (Why, then, is this permitted for Netilas Yadayim?)

Answer: They were not stringent to require this regarding Netilas Yadayim.

Implied Question: The Mishnah in Yadayim (1:3) says that if Dyo or Kankantum (types of ink) fell and their appearance changed, the waters are invaild. (Why is this being discussed as if Ameimar is the source of this law? It is an explicit Mishnah in Yadayim!)

Answer: Perhaps they though that the Mishnah in Yadayim was only regarding washing for Terumah.

Explanation: This implies that originally he wanted to say that even the first pouring does not need to be of a specific amount.

Question: This is difficult, as the Mishnah explicitly states, "the amount of a Revi'is for one!"

Answer: The Mishnah is referring to Terumah. The Gemara is deducing from it that just as an amount is not needed for the second pouring even regarding Terumah, it would seem that an amount is not even needed for the first pouring of Chulin. The Gemara concludes that Terumah is different, as it (the first pouring) comes from leftovers of purity (i.e. a Revi'is). (Accordingly, this cannot be applied to say that the first pouring of Chulin does not need a minimum amount.)

Explanation #1: Rashi explains that it was carved into a vessel.

Explanation #2: It would seem that even without carving it can have a Revi'is. Rather, it is slanted and does not sit straight, but instead leans like a covering of silver cups or jugs.

Explanation #2 (cont.): When the Gemara says "And he fixed it" it means that he widened it on the bottom until it sits straight without leaning. Before he fixed it, one was not able to use it for Netilah, as the place where it holds things is not significant. This is because if he would want to put water in it without it leaning in the right way, it would spill without being able to hold a Revi'is. The Gemara earlier said that one cannot do Netilah from a vessel that cannot hold a Revi'is.

Proof: In Yadayim (1:2), the Mishnah implies that the cover of a barrel is included in the (outside part of the) walls of a vessel that do not lack carving, but rather do not contain water unless they are leaned the right way as I have explained.

Observation: He holds like Rebbi Yehudah who requires a k'Beitzah, as he derives in Berachos (49b) from the Pasuk, "And you will eat and you will be satiated" that the Pasuk must be discussing eating that makes one full, meaning a k'Beitzah.

Observation (cont.): This is specifically afterwards. Beforehand, the implication is that he does make a Berachah. Similarly, Rebbi Meir who says that one does not make a Berachah on less than a Kzayis means that one does not say Birkas ha'Mazon. However, he makes a Berachah before eating even when it is less than a Kzayis. This is deduction is explicitly made by the Yerushalmi.

Implied Question: In Berachos (35a), we deduce that one must make a Berachah before eating based on a Kal v'Chomer from Birkas ha'Mazon. If one makes a Berachah when he is full, he certainly makes a Berachah when he is hungry! Even so, it is not possible to say Dayo (that we can only learn any Halachos in a similar fashion to this Kal v'Chomer), and therefore he makes a Berachah on a small amount even though he is not going to say a Berachah Acharonah. (Why not say it should be subject to the Kal v'Chomer?)

Answer: This Kal v'Chomer is (not a regular Kal v'Chomer which is a Torah law but rather) only a way to understand the Rabbinic enactment that one should make a Berachah Rishonah.

Proof #1: This is apparent from the Mishnah in Berachos (20b) that states that a Ba'al Keri makes a Berachah Acharonah but not a Berachah Rishonah (if it were a Torah law, he should make both).

Proof #2: Similarly, in Berachos (16a) the Beraisa states that workers that were working for someone and eating their bread should not make a Berachah Rishonah but they do recite the first two Berachos of Birkas ha'Mazon.

Question: How can we say this? One does not even need Netilas Yadayim for a k'Beitzah of Terumah, as they permitted a napkin to be used for those who ate Terumah (see 107b that Rav Tachlifa says this is permitted in general, even for more than a k'Beitzah).

Proof: This is apparent from the fact that Rebbi Tzadok was a Kohen, as is apparent from the Gemara in Berachos (20b) regarding the statement, "We skipped over coffins (to see the king)." This is also apparent from the Gemara in Bechoros (36a), regarding a Bechor owned by Rebbi Tzadok. Similarly, we find in Yevamos (15b) that he used to eat Chulin as if he needed to maintain the purity of Terumah. (In other words, Rebbi Tzadok was always eating Terumah or as if he was eating Terumah, and we know one can use a napkin for even a k'Beitzah of Terumah. Why would the Gemara make such a deduction when it knows the Gemara later (107b) that one can use a napkin for Terumah?)

Answer: The Gemara indeed could have said, "And according to you..." (and pointed this out). (The Maharam says that this answer erroneously appears in the text of Tosfos due to students mistakenly putting it into Tosfos. The correct text is that Tosfos does not answer the question at all.)

Explanation: This means that he ate it (the meat) with bread.

Explanation #1: Rashi explains that Shivsa is an evil spirit that is on hands that have not been washed in the morning.

Opinion: Rabeinu Tam explains that even if one does not have to give bread to a child on Yom Kippur he is allowed to wash his hands on Yom Kippur morning, as it is not worse than if his hands were dirty with plaster and excrement. In such a situation we say that one is allowed to wash normally and not worry (that he is transgressing the prohibition against washing on Yom Kippur).

Opinion (cont.): There is nothing dirtier than not washing one's hands in the morning, as one cannot touch his mouth, eyes, nose, and ears without doing so. This is as stated in Shabbos (109a) that if he does so (touches these areas before Netilas Yadayim in the morning) the evil spirit called Bas Melech rests on his hands (and can cause his harm).

Explanation #2: Shivsa here can be explained, as it is explained by Rabeinu Chananel, as an evil spirit that rests on food (for example) when one touches the bread that he is going to give to a four or five year old child, causing him to choke if he did not wash his hands at that time, even though he did wash his hands when he woke up in the morning.

Implied Question: We are not careful about this (not to give bread to a four or five year old child without washing our hands first). (Why not?)

Answer: This is because that evil spirit is not commonly found amongst us. This is similar to the reason why we are not careful regarding Zugos (having things in pairs) and regarding Giluy.

Opinion #1: If something is separating them, it is not within "one Tefisah (grabbing)." This term is used here in the same way that it is used in Avodah Zarah (50a) regarding Markolis stones when it says, "This case is within one grabbing, and this case is within two grabbings. What is the case (of two)? It is when there is a pile in between them."

Opinion #1 (cont.): Therefore the custom nowadays is that when one person is eating meat and one is eating cheese on one table, a loaf of bread or pitcher or other vessels are placed between them to separate them. Alternatively, one of them eats on a different tablecloth, as this also makes it akin to two "grabbings."

Opinion #2: Some explain that "they only forbade one grabbing" means that they share their expenses. This is akin to the case in Bava Basra (137b) which is about two brothers who bought an Esrog from the money of their estate.

Opinion #2 (cont.): The Gemara asks, do you think they really bought it with the same Tefisah? Why should it make a different if they have one expense or two different expenses if they know each other? The Gemara answers, like one Tefisah means that they recognize each other.

Observation: According to this explanation, the Gemara is not saying that it is permitted to eat on one table together with something interrupting between them (rather it is saying they may only eat together because they do not know each other).