(R. Yochanan): R. Eliezer and Sumchus argue about whether he brings Asham Taluy:

(R. Zeira): R. Eliezer compares this to a man who is unsure if he ate Chelev or permitted fat. He brings an Asham Taluy;

This is not only like the opinion that the Tzibur brings the Korban, so (due to the collection) the mistake becomes known;

Rather, it is even like the opinion that Beis Din brings it. Had he asked, he would have heard.

(R. Yosi bar Avin): Sumchus compares this to a man who transgressed, and offered his Korban Bein ha'Shemashos (twilight. It is a Safek whether it is day or night.)

If it was still day, he fulfilled his obligation. If it was night, he did not. He is in doubt, but he does not brings an Asham Taluy,

This is not only like the opinion that Beis Din brings the Korban, so the mistake does not become known;

Rather, it is even like the opinion that the Tzibur brings. He is exempt, for he acted according to the Hora'ah. He did not think to ask why a Korban was brought.

(Mishnah - Ben Azai): What is the difference whether he was at home or travelling?

Question: Why does Ben Azai argue? R. Akiva gave a fine answer (someone at home could have asked if Beis Din retracted)!

Answer (Rava): They argue about one who started to travel

Ben Azai obligates, because he is still inside his house (Rashi - the city);

R. Akiva exempts, because he is occupied with his journey, therefore he did not ask.

(Mishnah): If the Hora'ah totally uprooted a Mitzvah...

(Beraisa): "V'Nelam Davar" excludes when the entire Mitzvah was uprooted:

Suggestion: If Beis Din said that the Torah does not forbid Nidah or Melachah on Shabbos or idolatry, they are liable.

Rejection: "V'Nelam Davar", but if the entire Mitzvah was uprooted, they are exempt;

Suggestion: In the following cases, they are exempt: they forbade Nidah, but exempted one who has relations with a Shomeres Yom k'Neged Yom; they forbade Melachah on Shabbos, but exempted one who transfers from Reshus ha'Yachid to Reshus ha'Rabim), or if they forbade idolatry, but exempted one who bows.

Rejection: "V'Nelam Davar" - they are liable for permitting part of a Mitzvah.

Question: The Tana said that Beis Din is exempt if they uprooted the entire Mitzvah, then suggested that they are exempt for uprooting part. If so, when would they be liable?!

Answer: The Tana thought that "Davar" connotes (uprooting) the entire Mitzvah, so they should be liable totally uprooting, and exempt for uprooting part.

Question: The Tana answered "v'Nelam Davar." How does this imply part of a Mitzvah?

Answer #1 (Ula): We read it as if the 'Mem' of "v'Nelam" was also part of the word "Davar", making 'mi'Davar' (part of a matter).

Answer #2 (Chizkiyah): "V'Asu Achas mi'Kol Mitzvos" - not the entire Mitzvah.

Question: "Mitzvos" is plural. "Achas mi'Kol Mitzvos" refers to one of them!

Answer (Rav Nachman bar Yitzchak): (We expound according to the way) it is written. It is written "Mitzvas" (singular).

Answer #3 (Rav Ashi): We learn from a Gezerah Shavah "Davar-Davar" from Zaken Mamrei:

Regarding Zaken Mamrei it says "Ki Yipalei... Lo Sasur Min ha'Davar." Just like there, he is liable for uprooting part, also Beis Din is liable for this.

(Rav Yehudah): Beis Din is liable only if they permitted something that the Tzedukim (who do not rely on our Oral tradition) permit. If the Tzedukim know that it is forbidden, Beis Din is exempt.

Question: What is the reason?

Answer: Such a law is explicit in the Torah. People should not have relied on the Hora'ah.

Question #1 (Mishnah): (If Beis Din) forbade Nidah, but exempted one who has relations with a Shomeres Yom k'Neged Yom (they are liable);

This is explicit in the Torah! "V'Sofrah Lah" - she must count one day (without seeing blood, and refrain from relations on the day) corresponding to a day that she sees blood (during the days of Zivah! Tosfos ha'Rosh - it was known that the Tzedukim admit to this, for "Lah" is extra. R. Chananel, Tosfos - the correct text learns this law from "Mishkav Nidasah Yihyeh Lah.")

Answer #1: Beis Din permitted Ha'ara'ah (the first stage of Bi'ah (relations)) and forbade full Bi'ah (with a Shomeres Yom).

Objection: Also this is explicit in the Torah - "Es Mekorah He'erah" (forbids Ha'ara'ah)!

Answer #2: Beis Din permitted Bi'ah Lo k'Darkah (Bi'ah in the anus) and forbade normal Bi'ah.

Objection: Also this is explicit in the Torah - "Mishkevei Ishah" (both kinds of Bi'ah have the same law)!

Answer #3: Beis Din permitted Ha'ara'ah of Lo k'Darkah, and forbade even Ha'ara'ah of normal Bi'ah and full Bi'ah Lo k'Darkah.

Objection: We could have said this about relations with a Nidah. Why did the Mishnah discuss a Shomeres Yom k'Neged Yom?

Defense of Answer #1: Really, Beis Din permitted Ha'ara'ah with a Shomeres Yom;

This is not explicit in the Torah. "Es Mekorah He'erah" forbids Ha'ara'ah with a Nidah, but not with a Shomeres Yom!

Answer #4: Beis Din said that a woman becomes a Zavah only if she sees blood during the days, and not if she sees at night. (The Tzedukim say that she is Tehorah, for it says "Kol Yemei Zovah.")

Question #2 (against Rav Yehudah - Mishnah): If Beis Din forbade Melachah on Shabbos, but exempted one who transfers from one Reshus to another, they are liable.

Transferring Reshus is explicit (in Nevi'im) - "v'Lo Sotzi'u Masa mi'Bateichem"!

Answer #1: The verse forbids taking from Reshus ha'Yachid to Reshus ha'Rabim. Beis Din permitted the other direction.

Answer #2: The verse forbids carrying from Reshus to Reshus. Beis Din permitted passing or throwing something from Reshus to Reshus.

Question #3 (Mishnah): If they forbade idolatry, but exempted one who bows...

This is explicit - "Lo Sishtachaveh l'El Acher"!

Answer #1: They forbade bowing to idolatry normally served by bowing. They permitted bowing to other idolatry.

Answer #2: They forbade spreading the hands and feet while bowing. They permitted bowing without doing this.

Question (Rav Yosef): If they permitted plowing on Shabbos, what is the law?

Since they acknowledge the other Isurim of Shabbos, this is like uprooting part and keeping part;

Or, since they totally permit plowing, is this like uprooting the entire Mitzvah?

Answer #1 (Mishnah): (If they ruled that) the Torah forbids a Nidah, but exempts one who has relations with a Shomeres Yom k'Neged Yom, Beis Din is liable.

They are liable, even though they uprooted the entire law of Shomeres Yom k'Neged Yom!

Rejection (Rav Yosef): We can answer like we did above. (The case is, they permitted one who saw blood at night, or exempted Ha'ara'ah with a Shomeres Yom k'Neged Yom.)

Answer #2 (Mishnah): (If they ruled that) the Torah forbids Melachos on Shabbos, but exempts one who transfers from Reshus ha'Yachid to Reshus ha'Rabim (Beis Din is liable).

They are liable, even though this uproots the entire law of Hotza'ah (transferring Reshus)!

Rejection (Rav Yosef): We can answer like we did above. (They forbade transferring from a Reshus ha'Yachid to a Reshus ha'Rabim, but permitted the other direction, or throwing or passing.)

Answer #3 (Mishnah): ... The Torah forbids idolatry, but one who bows is exempt.

Beis Din is liable, even though this uproots the entire Isur of bowing!

Rejection (Rav Yosef): We can answer like we did above. (Beis Din forbade spreading the hands and feet while bowing, and permitted bowing without doing this.)

Question (R. Zeira): If they ruled that Shabbos does not apply during Shemitah, what is the law?

Question: Why would they make such a mistake?

Answer: They expounded "in plowing and reaping you will rest" - Shabbos applies only in years when you may plow and reap.

(Explanation of question): Do we say that since they acknowledge that Shabbos applies during other years, this is like uprooting part and keeping part;

Or, since they totally permit Shabbos during Shemitah, this is like uprooting the entire Mitzvah?

Answer (Ravina - Beraisa): If a prophet prophesizes to uproot a Mitzvah (he is a false prophet), he is killed;

R. Shimon says, if he uproots part of a Mitzvah, he is exempt;

Regarding idolatry, even if he says to serve it today and abolish it tomorrow, he is killed.

Inference: If they permitted (an Isur only at certain times, e.g.) Shabbos in Shemitah, this is like uprooting part. (R. Shimon expounds that regarding idolatry, he is liable for this.)

(Mishnah): In the following cases, Beis Din is exempt:

They ruled, and one of them said 'you are wrong';

The greatest Chacham of the Beis Din was not there;

One of them was a convert, Mamzer, Nasin, or too old to have children.

We learn from a Gezerah Shavah "Edah-Edah" from capital cases. Just like there, all the judges must be qualified to give Hora'ah, also here.

(Gemara) Question: What is the source that if the greatest Chacham was not there, they are exempt?

Answer (Rav Sheshes) Question: Why is Beis Din exempt if they permit something that even Tzedukim know is forbidden?

Answer: They are exempt because people should not have followed Beis Din. They should have known that it was a mistake;

Likewise, if the greatest Chacham was not there, people should not have followed Beis Din. They should have been concerned lest it is a mistake.

(Mishnah): We learn from a Gezerah Shavah "Edah-Edah" from capital cases. Just like there, all must be qualified (to give Hora'ah), also here.

Question: What is the source that in capital cases all must be qualified?

Answer #1 (Rav Chisda): "(The Sanhedrin that Moshe picked) will stand there with you" - they must be like you (Moshe, i.e. qualified).

Objection: Perhaps this teaches that they must stand with Moshe and not enter the Kodshei ha'Kodoshim! (Alternatively, they must be Tzadikim like Moshe, upon whom the Divine Presence can rest!)

Answer #2 (Rav Nachman bar Yitzchak): "They will bear with you" - they must be like you (qualified to rule).

(Mishnah): If Beis Din ruled b'Shogeg (mistakenly), and the people sinned b'Shogeg, Beis Din brings a Par;

If Beis Din b'Mezid ruled the wrong way, and the people sinned b'Shogeg, everyone who sinned brings a Kisvah or Se'irah;

If Beis Din erred, and the people sinned b'Mezid, they are exempt.

(Gemara) Inference: They are exempt (in the Seifa) only when Beis Din erred, and the people sinned b'Mezid;

Had they sinned b'Shogeg like Mezid (i.e. they thought they were doing something permitted, and they actually did what Beis Din mistakenly permitted. This is like Mezid, for they did not rely on the Hora'ah), they are liable! (Rashi - the people bring Chata'os; Tosfos Rosh - a Par is brought, and the people are exempt.)

Question: What is the case?

Answer: Beis Din permitted Chelev, and people accidentally ate Chelev, i.e. they confused it with permitted fats.

Suggestion: This was Rami bar Chama's question. We can settle it from our Mishnah!

Rejection: Perhaps the inference is not true. Rather, even if they were Shogeg like Mezid, they would be exempt;

The Tana taught 'Beis Din erred, and the people sinned b'Mezid' for parallel structure with the Reisha.