(Mishnah): If one is forbidden by an Isur Mitzvah or Kedushah... (they do Chalitzah, but not Yibum).

Question: R. Shimon said that sisters do not do Chalitzah or Yibum!

Answer: It is a decree that they do Chalitzah, due to Isurei Mitzvah or Isurei Kedushah who fall without a sister.

Question: This explains why the one forbidden (Isur Mitzvah or Kedushah) needs Chalitzah. Why does her sister also need Chalitzah?

Answer: We decree about her sister due to her (lest people think that also she does not need Chalitzah).

Question: Regarding Ervah, we do not decree!

Answer: Ervah is well known.

(Mishnah): Reuven and Shimon were married to Rachel and Leah (sisters); Levi (another brother) was single. Reuven died, Levi gave a Ma'amar to Rachel, and then Shimon died;

Beis Shamai say, Levi keeps his wife (Rachel). Leah is Achos Ishto (she does not need even Chalitzah);

Beis Hillel say, he sends his wife away with a Get and Chalitzah, and does Chalitzah to Leah.

In this case, they said 'Woe to him! He loses his wife and his brother's wife.'

(Gemara) Question: What case does this come to exclude?

Answer: This teaches unlike R. Yehoshua (109a. If a man was married mid'Rabanan to Leah, an orphaned minor, and her sister fell to him to Yibum mid'Oraisa, R. Yehoshua says, he cannot keep either one.)

Rather, we follow R. Eliezer (we counsel Leah to do Mi'un) or R. Gamliel (if Leah does not do Mi'un, when she matures her marriage becomes mid'Oraisa, and the Yevamah is exempt even from Chalitzah, for she is Achos Ishto).

Version #1 (R. Elazar): Do not say that Beis Shamai hold that a Ma'amar totally acquires a Yevamah, and afterwards he can divorce her with a Get (without Chalitzah);

Rather, a Ma'amar acquires only to dispel the Tzarah (so Rachel will not be considered Achos Zekukaso).

Support (R. Avin - Mishnah (26a) - Beis Shamai): If they both did Yibum, they may remain married.

This is only b'Di'eved.

If Ma'amar totally acquires, each brother may give a Ma'amar to a Yevamah and acquire her l'Chatchilah!

Objection: Even if Ma'amar only dispels the Tzarah, this is difficult! Each brother can give a Ma'amar to a Yevamah and dismiss her Tzarah, permitting Yibum l'Chatchilah!

You must say that only a Ma'amar of Heter dispels the Tzarah, but not a Ma'amar of Isur (e.g. to Achos Zekukaso);

Likewise, only a Ma'amar of Heter totally acquires, but not a Ma'amar of Heter!

Version #2 - Rav Ashi (R. Elazar): Do not say that Beis Shamai hold that a Ma'amar totally dispels, and the Tzarah does not need even Chalitzah. Rather, Ma'amar dispels partially.

Support (R. Avin - Mishnah - Beis Shamai): If they both did Yibum, they may remain married.

This is only b'Di'eved. If Ma'amar totally dispels, each brother may give a Ma'amar to a Yevamah and dispel her Tzarah, to allow Yibum l'Chatchilah!

Objection: In our Mishnah, Beis Shamai says that since he gave a Ma'amar, when her sister falls she is exempt due to Achos Ishto!

You must say that Ma'amar fully dispels the Tzarah only if the Yevamah could do even Yibum.

Question (Rava): According to Beis Shamai, does Ma'amar make Kidushin or Nisu'in?

Question (Abaye): What difference does it make?

Answer #1: If it makes Nisu'in, he inherits her, must become Tamei to bury her, and can annul her vows.

Rejection (R. Chiya's Beraisa): If an Arusah (a wife during Kidushin) died, her husband is not an Onen (forbidden to Kodshim mid'Oraisa that day, and exempt from Mitzvos until burial) over her. He may (or need) not become Tamei for her, and he does not inherit her. If he died, she is not an Onenes over him and need not become Tamei for him. She collects a Kesuvah.

If he only gave her a Ma'amar (which is only mid'Rabanan), all the more so he does not inherit or become Tamei for her!

Answer #2: If Ma'amar makes Kidushin, she must be given over (willingly) to Chupah. If it makes Nisu'in, she need not.

Objection: Without a Ma'amar, the Torah permits Yibum against her will - "Yevamah Yavo Aleha". Surely a Ma'amar does not change this!

Answer (Rava): Indeed, perhaps a Ma'amar changes this! When he gives a Ma'amar, the Zikah of Yibum departs, and she is like an Arusah (awaiting Nisu'in).

Answer (Beraisa - R. Eliezer): A Yavam can annul the vows of a Yevamah, whether there are one or two Yevamim;

R. Yehoshua says, he can annul if there is one Yavam, but not if there are two;

R. Akiva says, even if there is one Yavam he cannot.

Question: Granted, R. Akiva holds that Ein Zikah even when there is one Yavam, and R. Yehoshua holds that Yesh Zikah when there is one Yavam, but not when there are two;

However, how could R. Eliezer hold that Yesh Zikah when there are two Yevamim? (We cannot consider her to be Mekudeshes to both!)

Answer (R. Ami): The case is, he gave a Ma'amar. He holdsa like Beis Shamai, who say that a Ma'amar acquires totally.

Summation of answer: If Ma'amar makes Nisu'in, this explains why he can annul her vows. However, if it makes only Kidushin why can he?!

(Mishnah): The father and husband of a Na'arah Me'orasah (together) can annul her vows.

Rejection (Rav Nachman bar Yitzchak): (Perhaps Ma'amar makes Kidushin.) R. Eliezer said that he can annul her vows, i.e. together with her father!

Question: According to R. Elazar, who says that Ma'amar only dismisses the Tzarah, why can he annul in partnership?

Answer #1: R. Elazar meant that Ma'amar does not fully acquire regarding Zikas Yibum. If he will not do Yibum, Chalitzah is required. He could agree that it acquires totally regarding vows!

Answer #2 - Counter-question: Rav Nachman bar Yitzchak says that the Yavam and father annul together. However, the Beraisa says 'he annuls', not 'they annul'!

Answer: You must say that she took him to Beis Din (because he did not want to do Yibum nor Chalitzah), and Beis Din obligated him to feed her;

(Rav Pinchas): A woman vows on condition that her husband will approve. (Here, since the Yavam feeds her, she vows on condition that he will approve.)