Support #1: And even if Rabanan argue with him, and hold that its name is Pras, in any case we support him from what R. Meir taught, that its waters are Parim v'Rabim. They do not argue about this reasoning that a river is blessed from its source. They could hold that it is called Pras for this reason itself!

However, it is reasonable to say "why is it called Pras?" only according to R. Meir, for R. Meir holds that it has another name. Rabanan hold that Yuval is like "Yivlei Mayim" (it is not the river's name).

Support #2: And also in Bereishis Rabah it expounds like R. Meir. It says that Chidekel [is called so] because its waters are Chad and Kalim (hard and fast). Pishon [is called so] because [its waters] make Pishtan (flax) grow. Pras [is called so] because its waters are Parim v'Rabim.

Support #3: And without rain, rivers and springs get bigger, like we say in Rosh Hashanah "in Iyar, when Mazal Kimah rises during the day, and springs increase";

In Cheshvan they get smaller due to withholding of rain, for there was no rain all summer, and like we say in Pesachim (94b) that in Tishrei, Cheshvan and Kislev, the sun goes near the seas in order to dry the rivers.

Note: We expect rain to come to in Cheshvan, and we fast if there is no rain! Perhaps "withholding of rain" means that the ground, which is dry because there was no rain all summer, absorbs the rain, and does not emit it to rivers. Tosfos supports this from Pesachim. The sun goes near the seas in order to dry the rivers. I.e. it evaporates some of the water or warms it, causing that the land will absorb less and emit less to rivers. - PF)

Support #4: In Ta'anis (25b) we say that there is no Tefach of rain that descends [from above] for which two Tefachim do not rise corresponding to it from below;

And just like the ground gets twice as wet from below [as from above] when the rain descends, the same applies to increase of rivers. The water increases and grows from below when the rain descends from above;

This is like we say there also that the upper depth says to the lower depth "make your water flow."

Question: If so, what is the source that Rav argues with him, because Rav said that [the Pras testifies to] rain in Eretz Yisrael? Perhaps it is because then the source is blessed, like I explained!

Answer: It is because if it were true that he holds that it is normal to be blessed from its source, if so also without rain, sometimes it is blessed. If so, how is the river a witness? This is not testimony!

Question #1 (R. Tam): According to Shmuel, who says that the only water that is Metaher b'Zochalin is the Pras in Tishrei, and according to Rav and Shmuel's father, the Mishnah in Parah (8:10), and it is brought in Sanhedrin (5b) is difficult!

Water of Karmiyon and water of Pigah is Pasul for Mei Chatas because they are swamp water. Water of the Yarden and Yarmuch are Pasul, for they are waters of mixture;

Inference: If not for this, they would be Kosher. We do not disqualify lest dripping water be the majority over Zochalin, and rainwater is the majority!

Answer #1: They hold that these four rives are higher, for Eretz Yisrael is higher than all [other] lands, and rainwater does not remain there.

Question #2 (R. Tam): Rav, Shmuel's father and Shmuel hold that the only water that is Metaher b'Zochalin is the Pras in the days of Tishrei. How do Zavim and Metzora'im become Tahor, and how are they Mekadesh Mei Chatas on Erev Pesach?

Note: What is the last question? Perhaps they took from the river in Tishrei, and used it for Haza'ah on Erev Pesach! Perhaps Tosfos asks from the first Erev Pesach (i.e. before Pesach. The Kidush was not on Erev Pesach, for if so, people would be Tamei until the second Haza'ah four days later!) They could not be Mekadesh the water before burning the first Parah Adumah in Nisan. Melachah or Hesech Da'as disqualifies the water before Kidush. It is unreasonable that someone took water in Tishrei, and did not cease guarding it until Nisan! Or, perhaps the words "and how are they Mekadesh Mei Chatas" should be deleted here. Below Tosfos asks about where and when they got water for Mei Chatas.

We say in Pesachim (90a) that a Zav can immerse on Erev Pesach!

And how did they do Haza'ah on the people who did Pesach Sheni, and on all who died in the Midbar, and Misha'el and Elitzafon (who took Nadav and Avihu from the Mishkan)? They were far from the Pras and from Tishrei!

Partial Answer: According to what he explained that these four rives are higher, it is not difficult from Zavim and Metzora'im on Erev Pesach (we are not concerned lest the majority is rainwater). However, it is difficult from Kidush of Mei Chatas, for [these rivers] are (swamp water, which is) Pasul for Mei Chatas!

Answer #1 (R. Tam): Perhaps [all] rivers and streams that are high, rain does not mix with them, for the rain mixes with and descends in the low rivers and it is washed away and goes to the sea. They do not mix with high places. (There are other high rivers of normal water. They are Kosher for Mei Chatas);

And also [concern for mixing is] not in covered water, e.g. rivers that exude from caves. Rainwater does not mix and enter there.

Proof: The Mishnah (Parah 8:11) teaches that the well of Achav and the Pamyas cave are Kosher, and all the more so other wells and springs, like the Seifa teaches "a well into which fell Charsis (a kind of earth, crushed bricks, or plaster) or earth, he waits until it clears [before immersing in it]. R. Yishmael says so. R. Akiva says, he need not wait";

However, it needed to teach about the well of Achav and the Pamyas cave that they are Kosher, because the Yarden descends from the Pamyas cave, and the Yarden is Pasul, because it has mixed water. The Mishnah teaches unlike one might have thought; [rather,] the Pamyas cave is not mixed water. However, all agree that other wells are Kosher. (Tosfos did not explain why Be'er Achav was taught. Tiferes Yisrael explains that it was connected to a stream. It did not look like it flows, rather, like a Stam well, which is not Mayim Chayim. Even so, it is Kosher. However, Tosfos proves that Stam wells are Kosher!)

Answer #2 (R. Tam): We can say that according to letter of the law, Rishon Rishon (every drop that mixes in is) Batel, even according to Rav and the father of Shmuel. However, they are stringent due to Mar'is Ayin (lest onlookers think that they immerse in Pasul water), due to a stream of falling rain.

Consequence: According to Answer #2, the question from all [those who were Tamei Mes] in the days of Moshe is not difficult. Rabanan had not yet decreed.

Answer #3: It seems that [the rainwater] is Batel in a majority, for all rivers are connected to the Yam ha'Gadol more than [the connection needed for] joining Mikva'os;

The beginning of the rivers are not Ketarfes (water flowing down an incline), for this is the way they flow. Ketarfes does not join them, rather, the sea joins them. R. Tam explained all this in a Teshuvah.

Limitation: That reason "Rishon Rishon Batel" cannot be according to what I explained above (22a) that every Isur that is Batel, it is Chozer v'Niur when it increases to the point that there is a Shi'ur to forbid.

Observation: However, the reason that they are connected to the Yam ha'Gadol, it is possible.

Implied question: Why is this unlike a barrel of water that fell into Yam ha'Gadol? We say in Makos (4a) that one who immersed there, the Tevilah was invalid!

Answer: There, [what fell in] is intact without a mixture at all. However, here, the Notfim are not recognized.

Question: We do not judge possible from impossible, like R. Akiva said in Menachos (82a)!

Answer: There, in a Binyan Av he does not learn Pesach Doros from Pesach Mitzrayim. However, here it is a Hekesh, and R. Akiva agrees.

Source: We say in Nidah (37b) "you are forced to say that the verse equated them."

Question: Also in Menachos, we conclude that R. Eliezer's reason is due to "v'Avadta" - all the Avodos of the month (both in Mitzrayim and for Doros) are the same. It is proven there that it is a Hekesh, and even so R. Akiva argues with him, and did not accept to learn like him!

Suggestion: This is because R. Akiva does not agree that it is a Hekesh.

Rejection: In Pesachim (96a) we equate them to each other. For several matters we learn what is the difference between Pesach Mitzrayim to Pesach Doros!

Answer: Since the Hekesh is needed for other matters, it is not appropriate to say there "you are forced to say that the verse equated them" regarding possible from impossible.

Question: According to R. Achdevoy bar Ami, who says in Nidah (37b) that it is R. Eliezer who says that we learn possible from impossible, and he argues with the answer "you are forced to say that the verse equated them", what will he answer here?

Answer #1: He will establish it like R. Eliezer.

Answer #2: He needs the Hekesh of Nidah to other matters. Therefore, he does not establish it like R. Akiva. (Here, it is not needed for anything else.)

Question: It is difficult from "we do not divide lashes" (every Ed Zomem gets the full amount of lashes that he intended to obligate the defendant - Makos 5a). We learn lashes from Misah, which is possible from impossible, and the Gezeirah Shavah there is needed for several matters!

Question: Above (26b) we expound about Bechor 'the verse says "Ken Ta'aseh" - it added an extra action' (one keeps a calf longer before giving it to a Kohen than for Tzon)!

Answer: We expound it for a Bechor because it is written about Bechor, but since the Torah used an expression of doing, we expound it for Ma'aser, because regarding Bechor, Kedushah of action does not apply.

Explanation #1: This is not precise. The same applies [if he bought them already] born, as long as they are Mechusar Zman.

Explanation #2: It mentioned in their mothers' womb, to say that even according to R. Shimon ben Yehudah, who says that Mechusar Zman enters the pen for Ma'aser [so one who buys an animal within eight days, it is exempt from Ma'aser, one who buys a fetus, it is not exempt].

Question: Rava said in Bava Kama (70b) that the Torah forbade an Esnan, and even if he had Bi'ah with his mother (so he is exempt from paying, due to Kam Lei bid'Rabah Minei, since he is Chayav Misah. If he pays, it is an Esnan. His mother is a Yisraelis!)

And in a Beraisa in Temurah (29b), Rebbi says that Esnan is only for a woman always forbidden to him, but [not] his wife when she is Nidah... (here we say that it never applies to a Yisraelis)!

Answer: We do not discuss [here] when she is an Isur Ervah to him. We discuss only [women] on whom Kidushin takes effect, like it explains the reason. Therefore, her Esnan is permitted.

Implied question: [If she is not Ervah,] why is a Kohen lashed for Bi'ah with her?

Answer #1: E.g. she is a convert or freed Shifchah, who is a Zonah, or she became a Zonah through another man, that she was forbidden to him with an Isur Kares. Since he had Bi'ah with her, he made her a Zonah.

Answer #2: Or, it is like the opinion that a bachelor (the same applies to a married man; it says so for parallel structure with Penuyah) who had Bi'ah with a Penuyah not for the sake of Kidushin, he made her a Zonah.

Implied question: It connotes that we do not find a Zonah Yisraelis that she tithes the Esnan. We could find this through an Isur Ervah!

Answer #1: He comes to teach that a Zonah Yisraelis, her Esnan is permitted [when she is not Ervah].

Question: Rava said in Temurah (29b) that the same applies to a Nochri Zonah or a Yisraelis Zonah - her Esnan is forbidden. The Beraisa is difficult for him!

Answer: It was not taught in the academy of R. Chiya and R. Oshaya. (Therefore we cannot challenge from it, for perhaps it is errant.)

Answer #2: It could properly have said that she tithes it. Rather, [the Tana] teaches [that he tithes it when he bought it back] to teach that [that one tithes an animal] bought in its mother's womb, like R. Yochanan.

Disclaimer: However, this Chidush (R. Yochanan's law) we learn also when she tithes it, when he gave it to her in its mother's womb, and it is not exempt due to something bought or given for a gift!

Question: Since we learn from Arayos, we should exclude a Nochris Zonah, for we require similar to Arayos, that his Kidushin does not take effect on her, but others can be Mekadesh her. This excludes a Nochris Zonah. Neither he (the Bo'el) nor others can be Mekadesh her!

This is like we say in Yevamos (45a), according to the opinion that a Nochri or slave who has Bi'ah with a Bas Yisrael, the child is Kosher, for it is unlike Arayos for this reason (Arayos do not have Kidushin with each other, but they have Kidushin with others. A Nochri or slave does not have Kidushin with anyone).

And Rava himself, who obligates for a Nochris, in Temurah (29b), holds in Yevamos (45b) that the child is Kosher!

Answer: Regarding a Nochris Zonah, since there is no Kidushin with her at all, all the more so it causes the name "Zenus" on her;

However, regarding Mamzerus, the child should not be a Mamzer, since she is not proper for another man more than this one.

Explanation: [Bechorah applies to partners,] like it is written "uv'Choros Bekarchem v'Tzonchem." I explained above (2a DH veha'Mishtatef) why we need this verse. [Seemingly,] we should know this already from the need to exclude partnership with a Nochri! (Tosfos said there that from "b'Yisrael", which excludes partnership with a Nochri, we would not include partnership in the mother with a Yisrael, for "b'Yisrael" is written about the fetus.)

Implied question: Here R. Elazar argues with R. Yochanan, and above (22b) it connotes that he agrees that [brothers who divide] are buyers, for he answered "what does it mean that they do not return? [They do not return] to be Batel! (Rather, they return and divide again.)

Answer #1: Here we show why R. Yochanan needed to teach these two matters. (One does not follow from the other. It is not difficult if R. Elazar agrees with only one of them.)

Answer #2: Above, he needed to answer, lest the Mishnah be difficult for R. Yochanan.

Question: How will it help? It is not known which is in exchange for the dog!

Suggestion: It is the one worth as much as the dog!

Rejection: [There is a solution even when this does not apply, for the Gemara] said "if all are worth the same, indeed (he could pick one and say that it is in exchange for the dog)!" Then, how can he choose the one in exchange for the dog to permit the others?

Answer: The Gemara holds that since Yesh Bereirah, the matter should depend on his intent. Presumably, his intent from the beginning was that the one that he will choose, it is in exchange for the dog.