(Beraisa) Question: What is the source that one Zerikah on the outer Mizbe'ach is Mechaper (even when two or four Zerikos should be done)?

Answer: "V'Dam Zevachecha Yis'hafech" connotes one putting.

Gitin 10b (Rav Papa): Witnesses on a Get must sign in front of each other.

(Rav Ashi): This is a decree due to when the husband says 'all of you sign this Get.'

29a (Mishnah): If Reuven appointed Shimon to give a Get within Eretz Yisrael, and Shimon got sick, Shimon can appoint a Shali'ach to give the Get. If Reuven told Shimon to receive something from his wife when he gives the Get, Shimon may not make a Shali'ach. Reuven does not want his deposit to be in the hands of others.

(R. Yochanan): Sometimes, this disqualifies the Get (if Shimon makes another Shali'ach to give the Get and take the object). It is as if Reuven told Shimon 'divorce her only in the house', and Shimon divorced her in the attic, or 'divorce her only using the right hand', and he divorced her with the left hand.

If she gave to him the object before he gave the Get, the Get is valid. It is Pasul when Shimon told his Shali'ach 'take the object, then give the Get', and the Shali'ach gave the Get first. Even if Shimon himself did this, the Get is Pasul.

65a (Mishnah): If a man told a Shali'ach 'give this Get to my wife in Ploni (a certain place), and the Shali'ach gave it elsewhere, the Get is Pasul. If he told the Shali'ach 'give this Get to my wife. She is in Ploni', and the Shali'ach gave it somewhere else, it is valid.

If a woman told a Shali'ach 'receive my Get in Ploni', and the Shali'ach received it elsewhere, the Get is Pasul;

R. Elazar says, it is valid. If she told the Shali'ach 'bring my Get from Ploni', and the Shali'ach brought it from elsewhere, it is valid.

R. Elazar agrees in the Reisha, for a man decides whether he wants to divorce, so he can be particular about the place. A woman is divorced against her will. She cannot decide where the Get will be given. She merely suggests where she thinks that the Shali'ach can get the Get.

Nedarim 36a - Question: Granted, if a Kohen is a Shali'ach of Hash-m, his intent can make Pigul. (Hash-m made him a Shali'ach in every case.) However, if he is a Shali'ach of Yisrael, why is it Pigul? The owner made him a Shali'ach to help him, not to hurt him!

Answer: Pigul is an exception. It says "Lo Yechashev" - in any case.

Rambam (Hilchos Gerushin 1:24): It was enacted that witnesses must sign the Get in front of each other. If they did not, it is Pasul.

Perush ha'Rosh (Nedarim 36a DH ha'Makriv): The verse teaches that intent of the one who offers can disqualify, even though it is not his Korban.

Ran (Gitin 3b DH v'Hilchesa): Rashi holds that witnesses must sign in front of each other, lest the husband say 'all of you.' In such a case, if they did not all sign, it is Pasul, even though only two are for testimony. The Ramban says that since all of them are witnesses, all must sign

Shulchan Aruch (EH 120:9): If he says 'all of you sign a Get for my wife', the first two are witnesses, and the rest are to fulfill his Tanai. The rest may sign on a later day, but they must sign in front of all of them. Even if they sign the Get after the Get was given, (Rema - even after she remarried), it is Kosher.

Chelkas Mechokek (23): The Ran holds that even if a witness died before the rest signed, it is Kosher, for only l'Chatchilah they must sign in front of each other. Tosfos holds that perhaps it is Pasul mid'Rabanan if they did not sign in front of each other.

Shulchan Aruch (130:13): Witnesses on a Get must sign in front of each other. If they signed not in front of each other, it is Pasul.

Shulchan Aruch (141:45): If a Shali'ach deviated from what the husband or wife told him, he did not do anything. If a man said 'give this Get to my wife in Ploni', and the Shali'ach gave it elsewhere, or 'give it to her only in the upper story', and he gave it in the house, or vice-versa, or 'give it to her only using the right hand', and he gave it with the left, he did not do anything.

Beis Shmuel (62): There is reason to say that he is particular about where he gives the Get, therefore deviation disqualifies even if he did not say 'give it only in Ploni.' Regarding giving it in the upper story or using the right hand, we say that he is particular only if said 'gave it only in this way.'

Pischei Teshuvah (48): Toras Gitin asks that regarding an Eruv, if he said to put in the upper story we say that he is particular, even if he did not say 'only'. Also, since there was no need to mention the upper story, this shows that he was particular about it!

Zayis Ra'anan (2:39): If a Shali'ach did something that is not l'Chatchilah, but b'Di'eved the Get is Kosher, the Shlichus is not Batel. We learn from one who told 10 to sign a Get. Even though l'Chatchilah they must sign in front of each other, the Ran holds that the Get is Kosher (if they did not). Also when one told two to sign, if they signed not in front of each other, it is Pasul only mid'Rabanan. According to the Rif, who holds that Edei Chasimah by themselves work according to R. Elazar, Shlichus is required. The entire Get should be Batel because there is no Shlichus! Even if according to the Ri, Shlichus is not required for signing, the Get should be Batel because they deviated from his command. Also, we find that a Shali'ach may make another Shali'ach to give the Get only if he became sick. However, b'Di'eved the Get is Kosher (even if he was not sick and made another Shali'ach), and it is not considered changing the Shlichus.

Note: it seems that he learns from R. Yochanan, who disqualifies one who made another Shali'ach only when the husband was particular that the Shali'ach receive something from her.

Zayis Ra'anan: This is when they did not deviate from his words, just they did not complete the Shlichus regarding a matter of law. Therefore, there is no distinction between his Shali'ach and hers. If a Shali'ach deviated from the husband's words, if there is even if a remote chance that he is particular, the Get is totally Batel, like the Shulchan Aruch says. One can prove this from Yoma 19b, which asked whether Kohanim are Sheluchim of Yisrael or of Hash-m. Why didn't the Gemara learn from many Mishnayos in Zevachim which say that a deviation is Pasul only if there is a second verse for it? (If Kohanim are Yisrael's Sheluchim), the Korban should be Pasul because the Shlichus is Batel! Rather, a Shali'ach is no worse than the Meshale'ach. Just like a Kohen's own Korban would be Kosher b'Di'eved, the same applies to the Meshale'ach's Korban.

The questioner brought a proof from Korbanos Lo Lishmah, which are Kosher, according to Rashi, who requires Shlichus for Shechitah. One can reject the proof. Nedarim 36a says that if Kohanim are Sheluchim of Yisrael, they can make Pigul due to "Lo Yechashev." The verse teaches that the Shlichus is not Batel. My proof is from a deviation through an action, e.g. four Zerikos of blood are required, and he did only one. "Lo Yechashev" teaches only that deviation through thought does not cancel the Shlichus.

Ha'arah 9: The Rosh connotes that the verse teaches that intent of the one who offers can disqualify, even though his Shlichus is Batel. However, we can bring a proof from the Halachah that if Pigul was put on the Mizbe'ach, we do not take it down. If the Shlichus was Batel, we would take it down, for we require Shlichus for Shechitah! The proof from Korbanos that require four Zerikos is not so clear. There, his deviation was through inaction! Perhaps the proof is from the Halachah that if he did too many Zerikos, it is Kosher. This is deviation through action.