(Mishnah) Question: What is the case of Eshes Achiv she'Lo Hayah b'Olamo (the widow of a brother who died before the Yavam was born)?

Answer: Reuven and Shimon are brothers. After Reuven died, Levi (another brother) was born. Then, Shimon did Yibum with Chanah (Reuven's widow), and Shimon died;

The first wife is exempt because her husband was not alive in the life of the Yavam; the second wife (of Shimon, Leah,) is exempt because she is Chanah's Tzarah.

If Shimon [merely] gave a Ma'amar to Chanah [and after he died], Leah does Chalitzah but not Yibum.

(Gemara): "[Ki Yeshvu Achim] Yachdav exclude Eshes Achiv she'Lo Hayah b'Olamo.

Question: If not for this [Drashah], what would we say? If a man (Ploni) died without children [and without brothers], should his wife be forbidden to marry, lest his father have a son, and the widow will need to do Yibum?!

If so, even if [Ploni's] mother died, his wife should be forbidden to marry, lest his father marry another wife, and have a son, and the widow will need to do Yibum!

If so, the Torah should write 'u'Ven v'Av Ein Lo' (then, when there is a living brother, she does Yibum, and when there is no live brother, she is permitted l'Shuk, but when Ploni's father is alive, even if there is no live brother, she is forbidden l'Shuk)!

Answer: Rather, the case is, [Ploni] died and left his mother pregnant. Do not say that if [Ploni] died and left his wife pregnant, perhaps she need not wait to know whether it is a viable baby (and then exempt from Chalitzah or Yibum), or a Nefel [and she falls to Yibum? Surely she must wait!] Also here [that Ploni's mother is pregnant, Ploni's widow] should need to wait to know whether it is viable [and male, and then she falls to Yibum,] or not viable!

Therefore, the Torah needed to write Yachdav to exclude Eshes Achiv she'Lo Hayah b'Olamo. (Since Ploni had no brother when he died, his wife is exempt.)

Suggestion: "Yevamah Yavo Aleha" is Bi'ah. "V'Lakchah Lo l'Ishah" is Ma'amar. Perhaps just like Bi'ah finalizes her [marriage to the Yavam], also Ma'amar finalizes her!

Rejection: "V'Yibmah" - the entire Parshah is tied to (depends on) Yibum. Bi'ah finalizes her, but Ma'amar does not finalize her.

Question: If so, what effect does Ma'amar have?

Answer: It forbids her to the [other] brothers.

R. Shimon says, [it is a Safek whether] Ma'amar acquires or does not acquire.

Question: What is R. Shimon's reason?

Answer: "Yevamah Yavo Aleha" is Bi'ah. "V'Lakchah Lo l'Ishah" is Ma'amar. Just like Bi'ah finalizes her, also Ma'amar finalizes her;

Or, perhaps "Yevamah Yavo Aleha", and she is Lekuchah Lo (married to him), and the Ma'amar did not do anything to her.

R. Elazar ben Arach says, Ma'amar makes a full Kinyan in a Yevamah.

Question: What is R. Elazar ben Arach's reason?

Answer: "V'Lakchah Lo l'Ishah" - [Ma'amar] is like [regular] Kidushin of a woman. Just like Kidushei Ishah acquires a full Kinyan, also Ma'amar acquires a full Kinyan.

Question: What is Ma'amar of a Yevamah? 'You are Mekudeshes to me with money or Shaveh Kesef.'

Both Rabanan and R. Shimon agree [to the Seifa of our Mishnah (if he gave a Ma'amar, the other does Chalitzah but not Yibum);

According to Rabanan [who say that Ma'amar acquires partially], the part that Ma'amar acquired, correspondingly the Tzarah [is Tzaras Eshes Achiv she'Lo Hayah b'Olamo, and] is forbidden. The part that Ma'amar did not acquire, correspondingly the Tzarah [is like a regular Yevamah who fell to Yibum from the latter brother, and] is permitted. Therefore (since she partially fell to Yibum, but is partially forbidden), she does Chalitzah and not Yibum;

According to R. Shimon, if Ma'amar acquired, both women are forbidden [the widow of the first brother is Eshes Achiv she'Lo Hayah b'Olamo, and her Tzarah is Tzaras Ervah]. If it did not acquire, the first is forbidden, and the second is permitted. Due to Safek, she does Chalitzah and not Yibum.

Question: [Practically,] what is the difference between them?

Answer: If he had Bi'ah with the second - according to Rabanan it is Bi'as [partial] Ervah [Vadai, and she needs a Get and Chalitzah. according to R. Shimon it is Safek Bi'ah Ervah, Safek Kosher Yibum, so she needs only a Get. If she had any Zikah to Yibum, i.e. if Ma'amar does not acquire, she already did proper Yibum, so no Zikah remains.]

Inference: [The other does Chalitzah but not Yibum] because he did Ma'amar to her, but if he did not do Ma'amar to her, she can do Yibum.

Question: [The brother who was born before the first died,] does he not have Zikah to her?! (Even without a Ma'amar, she should be considered partially his wife due to Zikah, and the Tzarah is Tzaras Ervah!)

Answer (R. Chagai): I answered this like R. Yakov bar Acha said in the name of R. Lazar. If a Shomeres Yavam died, [the Yavam] is permitted to her mother. He had Zikah to her; once she died, the Zikah is Batel (so her mother is not considered his mother-in-law at all);

Here, since [the Yavam] died, his Zikah is Batel (so she is not considered his wife at all).