(Mishnah): Everything written in Megilah (Megilas Ta'anis, a list of Yamim Tovim mid'Rabanan) that one may not eulogize [on the day], the day before is forbidden, and afterwards is permitted;

R. Yosi says, before and after is forbidden.

[When it says] that one may not fast, before and after are permitted. R. Yosi says, before is forbidden and after is permitted.

(Gemara): Our Mishnah is R. Meir, for R. Meir said that [days] that one may not eulogize, fasting is forbidden. [Days] that one may not fast, eulogies are permitted. If it says Stam [Asur, only] fasting is forbidden. (He must permit the day before, for what is secondary, should not be like what is primary (the day itself).)

(R. Yonah): These days that one may not eulogize, on some of them fasting is forbidden.

R. Shimon ben Gamliel says, why does it say [in Megilas Ta'anis] "on them'' twice? This teaches that the night is permitted and the day is forbidden.

It was taught [at the end of Megilas Ta'anis] "except for a man who has on himself [a Chiyuv to fast on one of these days,] for he forbade himself in Tefilah.'' (His vow overrides Megilas Ta'anis.)

(R. Yosi bei R. Bun): He must mention the fast [in Minchah] of the previous day. (If not, this is not an acceptance.)

[This teaching] is like R. Ze'irah taught in the name of Rav Chunah - he says [Aneinu in every Tefilah,] like Shabbos (which we mention in Tefilah) at night and by day.

A Mishnah [in Megilah teaches that even though villagers may read the Megilah as early as the 11th of Adar, eulogies and fasting are permitted on those days. We can establish this only] for the 11th according to R. Yosi, or [even] on the 12th according to R. Meir.

Question: This is difficult for R. Yosi (even the 11th is forbidden)! Was it not taught [in Megilas Ta'anis] that the 12th of [Adar] is Yom Tiriyon. (If so, R. Yosi forbids also the day before!)

Answer (R. Yakov bar Acha): [The Yom Tov of] Yom Tiriyon is Batel, for it is the day when Lulainus and Papus (great Tzadikim) were killed.

Question: [Megilas Ta'anis says that] the 13th is Yom Nikanor. What is Yom Nikanor?

Answer: [Nikanor was] a top officer of the Greek kingdom. He was going to [fight in] Alexandria and saw Yerushalayim, and reviled, insulted and blasphemed, and said "when I return in peace, I will cut down this tower (the Beis ha'Mikdash)'';

Someone from Beis Chashmonai went out and was killing [Nikanor's] soldiers, until he reached [Nikanor's] wagon. Once he reached his wagon, he cut off his hand and cut off his head and stuck them on a piece of wood and wrote underneath "the mouth that spoke with sin, and the hand that stretched out with pride (he used to wave it against Yerushalayim - Bavli 18b), are hung on a pole opposite Yerushalayim.''

Observation: According to R. Yosi, this is fine. [Yom Nikanor] comes to forbid the day before.

Question: According to R. Meir, what does it come to forbid? He does not hold that the day before [Yom Nikanor is forbidden, since only fasting is forbidden on Yom Nikanor. The 13th] itself is forbidden due to the 14th [since even eulogies are forbidden on the 14th, it forbids the day before]!

Answer #1: It teaches that we may not eulogize [on the 13th].

Support (and retraction from the above Observation): And is it not difficult according to R. Yosi?! Was it not taught that the 12th is Yom Tiryon, and R. Yakov bar Acha said that Yom Tiryon ceased, for Lulinus and Papus were killed that day? (All the more so, we no longer say that due to the 13th, the 12th is a Yom Tov! Rather, also R. Yosi must say that Yom Nikanor comes to forbid eulogies on the 13th.)

Citation (Megilas Ta'anis): On the 14th and 15th is Purim, that one may not eulogize. On the 16th they began to build a wall around Yerushalayim. One may not eulogize.

Observation: According to R. Meir, this is fine. [It teaches about the 16th] to forbid [the day] itself.

Question: According to R. Yosah what does this come to forbid? He does not [need it to] forbid the day before (it is already forbidden due to Purim). It (the 16th) itself is forbidden due to the 15th! (This is the Tana R. Yosi. The Yerushalmi uses the names Yosi and Yosah [and Yosa] interchangeably. Below, an Amora R. Yosah answers this.)

Answer #1: It comes to teach that the day itself one may not eulogize. (Due to the 15th, we would forbid the 16th only for fasting.)

Citation (Megilas Ta'anis): On the 17th [of Adar] the nations came against the remnant of Chachamim in the land of Bolkin and Beis Zavdin, and there was a redemption for Beis Yisrael.

Observation: According to R. Meir, this is fine. It comes to forbid the day itself.

Question: According to R. Yosah what does this come to forbid? The day before he does not [need to forbid. The 16th itself a Yom Tov. The 17th] itself is forbidden [already due to the 16th]!

Answer (and Answer #2 to the previous questions - R. Yosah): All of these do not support nor refute R. Meir, and not R. Yosi. [Megilas Ta'anis] comes to list days that miracles were done for Yisrael (even if we would already know that they are forbidden due to the days before or after).

Proof: This must be so, for [Megilas Ta'anis] teaches that on Rosh Chodesh Nisan, the Tamid was established. (Chachamim refuted the Baisusim, who said that an individual may volunteer to bring it.) One may not eulogize. [This was taught] even though without this, it is forbidden due to Rosh Chodesh!

Distinction: However, Shabbos and Yom Tov, one may fast before them and after them.

Question: Why are you lenient about these, and stringent about these [of Megilas Ta'anis]?

Answer: These (Shabbos and Yom Tov) are mid'Oraisa. We need not strengthen Divrei Torah. These (of Megilas Ta'anis) are mid'Rabanan. They need to be strengthened.

Limitation: These (Isurim of fasting and eulogies) were before Megilas Ta'anis was Batel, but after [the Churban, that] Megilas Ta'anis is Batel, all these [days] are Batel.

(R. Chaninah and R. Yonason): Megilas Ta'anis is Batel.

(R. Ba and R. Simon): Megilas Ta'anis is Batel.

(R. Yehoshua ben Levi): Megilas Ta'anis is Batel.

Objection (R. Yochanan): Last night, I sat and taught an episode that they decreed a fast during Chanukah in Lud, and they said that R. Eliezer cut his hair, and R. Yehoshua bathed. R. Yehoshua told [those who fasted] "go fast [after Chanukah, to atone] for fasting [during Chanukah]!

And you say that Megilas Ta'anis is Batel?! (If so, there was no reason not to fast! This is difficult only if the episode was after the Churban. Perhaps R. Yochanan had a tradition that it was so. Alternatively, before the Churban, R. Yochanan ben Zakai was alive, and R. Yehoshua would not rule [that they must fast again] in front of his Rebbi.)

Answer (R. Ba): Even if you will say that [the rest of] Megilas Ta'anis is Batel, [the Isurim of] Chanukah and Purim are not Batel.

Support: The actions of Rabanan show that Megilas Ta'anis is Batel;

R. Yonason fasted every Erev Rosh Hashanah. R. Avun fasted every Erev Shabbos. (Megilas Ta'anis forbids to complete a fast on Erev Shabbos or Erev Yom Tov - SHA'AREI TORAS ERETZ YISRAEL.) R. Ze'irah fasted 300 fasts, and some say 900 fasts, and he was not concerned for Megilas Ta'anis.

R. Yakov bar Acha instructed teachers of children "if a woman (who brings her son to you) will ask you, tell her that one may fast on any day, except for Shabbos, Yom Tov, Rosh Chodesh, Chol ha'Mo'ed, Chanukah and Purim.''

(Mishnah): We do not decree a fast on the Tzibur initially on Thursday, lest it raise prices. Rather, the first three fasts are Monday, Thursday, and Monday, and the second are Thursday, Monday and Thursday;

R. Yosi says, just like the first do not [begin] on Thursday, also the second and last do not.

(Gemara - Shimon bar Ba): An episode occurred in front of R. Yochanan, and he ruled like R. Yosi (that one may begin a set of fasts on Thursday.) R. Elazar was pained. He said "he abandons the Stam [Mishnah], and does like an individual?!''

[Later,] R. Lazar found that R. Chiyah taught [the first Tana's opinion] in the name of R. Meir. When he heard that R. Chiyah taught it in the name of R. Meir, he said "the elder (R. Yochanan) knows how to answer for himself!'' (SHA'AREI TORAS ERETZ YISRAEL)

Question (R. Mana, to R. Yudan): Didn't R. Chizkiyah say in the name of R. Avahu in the name of R. Lazar "wherever Rebbi taught a Machlokes [in a Mishnah] and afterwards a Stam, the Halachah follows the Stam''? (The same applies here, that R. Chiyah taught a Machlokes, and Rebbi taught Stam.)

Answer #1 (R. Yudan): Is that not [when] Rebbi taught [both the Machlokes and the Stam? Perhaps [it is not when] another [taught one of them]!

Objection: If when we find that Rebbi taught an argument, and later he taught Stam, the Halachah follows the Stam - in a place that we do not find that Rebbi taught an argument, rather, others taught an argument, and Rebbi taught Stam, all the more so the Halachah should follow the Stam!

Strengthening of objection: Came R. Chizkiyah, R. Yakov bar Acha, and R. Shimon bar Ba in the name of R. Lazar, and [said] that even if others taught an argument, and Rebbi taught Stam, the Halachah follows the Stam.

Question: (If so, R. Lazar's question returns!) Why did [R. Yochanan] rule like an individual?

Answer #2 (R. Shmuel bar Yanai in the name of R. Acha): We say [that the Halachah follows the Stam] when the argument was not taught by (in the same Mishnah as) the Stam. However, when the argument was taught by the Stam (it is called Stam because one opinion is anonymous) the Halachah does not [necessarily] follow the Stam.

Answer #3 (R. Yosi bei R. Bun citing R. Acha): We say [that the Halachah follows the Stam when the argument is] an individual against an individual, but if an individual argues with Chachamim (and the Stam is like the individual) the Halachah [need] not follow the Stam.

(Mishnah): We do not decree a fast [initially] on Rosh Chodesh, Chanukah or Purim. If they began [a set, and a fast fell on one of these days, we fast, and] we do not interrupt. R. Gamliel says so;

R. Meir says, even though R. Gamliel says that we do not interrupt, he agrees that we do not complete the fast.

The same applies to Tish'ah b'Av that fell on Erev Shabbos.

(Gemara) Question: How much is considered that they began?

Answer #1 (R. Ba): It is one fast.

Answer #2 (R. Yosah): It is two.

In practice, we follow R. Ba's opinion.

Question: What do we read [in the Torah on a fast on Rosh Chodesh]?

Answer #1 (R. Yosah): We read the Brachos and curses [in Ki Savo].

Question (R. Mana): Is this in order to inform them that it is a fast?! They fall on their faces (in Tachanun, when a fast is on Rosh Chodesh), and they do not know that it is a fast [so we must read Brachos and curses to inform them]?!

Answer (R. Yosah): [It is not to inform them that it is a fast. I came] to inform you that [the proper Kri'as ha'Torah is] Brachos and curses. (We explained this like PNEI MOSHE.)

Answer #2 (R. Yudan Kapudkiya citing R. Yudah bar Pazi, in front of R. Yosi): They read [the normal reading for] Rosh Chodesh.

1. R. Yosah (to R. Yudah bar Pazi): Did you hear this from your father?

R. Yudah bar Pazi: My father said so only in Einei Tav (where they are Mekadesh Rosh Chodesh), they know [Vadai] that it is Rosh Chodesh, they read of Rosh Chodesh [to publicize the matter - PNEI MOSHE]. All other places read Brachos and curses.

(Beraisa): When Tish'ah b'Av falls on Erev Shabbos, one eats even one egg, and drinks even one cup, lest he enter Shabbos afflicted. R. Yudah says so;

R. Yosah says, he fasts and completes [the fast].

(R. Ze'irah citing Rav Yehudah citing R. Ba citing R. Imi bar Yechezkel citing Rav): The Halachah is like he says - he fasts and completes.

Question: Why didn't he say that the Halachah follows R. Yosah?

Answer: Some switch his opinion to that of Chachamim.

(R. Ze'irah citing R. Chunah): Even an individual who decreed a fast on himself on Erev Shabbos, he fasts and completes;

This is like Rav Bivi was sitting in front of R. Yosa. He wanted to learn from him this law. [Rav Bivi] said to him "I will go home soon.'' [R. Yosa] said "is it night [that you want to go home]?!'' He said "I am fasting.'' [R. Yosa] said [you need not go now to prepare food to eat at night]. "I have lupines'' (you can take them when you go. Rav Bivi) said [I learn from you that] we complete the fast, like R. Yosi. (HA'GAON RAV C. KANIEVSKY, SHLITA)