(Beraisa): After R. Eliezer died, four Chachamim entered to challenge R. Eliezer's words - R. Elazar ben Azaryah, R. Yosi ha'Gelili, R. Tarfon and R. Akiva.

(R. Yehoshua): You cannot refute the lion (R. Eliezer) after [his] death!

Question #1 (R. Tarfon): If he said to her 'you are permitted to every man except for Ploni', and she married Ploni's brother, and he died without children, how can Ploni do Yibum?! (Regarding him, she was never divorced!) It turns out he stipulated against something written in the Torah; his Tenai is Batel.

Objection: If so, one should not be able to marry his brother's daughter, lest he [die without children, and Yibum is uprooted, for the Yevamah is the Yavam's daughter, and he stipulated against something written in the Torah!

Answer (R. Yosi bei R. Bun): There, the Torah forbade [the Yevamah to the Yavam]. Here, he forbade her to him (through his stipulation in the Get).

Question (R. Chananyah citing R. Pinchas): We should teach 16 women (Arayos exempt their Tzaros from Chalitzah or Yibum, according to R. Eliezer, i.e. the 15 in the Mishnah Yevamos 1:1, and an Eshes Ish, through such a Get)!

Answer (R. Mana): The reason (answer) was already said. There (the 15 Arayos), the Torah forbade [and exempted the Tzarah] to the Yavam. Here, he forbade her to him (through his stipulation).

R. Eliezer agrees that if [he said 'you are permitted to every man except for Ploni', and] she married someone else and was widowed or divorced, she is permitted to the one (Ploni) to whom she was forbidden.

Inference: This shows that [her new husband's] death or divorce permits what the first forbade.

(R. Yirmeyah): He said only that his death or divorce [permits], but not his Nisu'in. (R. Tarfon said that if he died without children, Yibum is uprooted. If now she is permitted to Ploni, what is the reason? R. Yirmeyah holds that Nisu'in causes the fall to Yibum, and at the time of Nisu'in, she was forbidden to Ploni due to her first husband. We explained this like SEFER NIR.)

Question #2 (against R. Eliezer - R. Yosi ha'Glili): Do we find in the Torah that what is forbidden to this [person] is permitted to that one, and what is permitted to this one is forbidden to that one?! What is forbidden to one is forbidden to everyone. What is permitted to one is permitted to everyone!

Question #3 (R. Akiva): If the one to whom she was forbidden (Reuven divorced her to all, except for Ploni) was a Kohen, and [Reuven] died, she is a widow to Ploni (regarding him, she was not divorced) and a divorcee to all his Kohanim brethren!

What was the Torah more stringent about, a divorcee or a widow? It is more stringent about a divorcee (she is forbidden to all Kohanim. A widow is forbidden only to a Kohen Gadol);

[The Isur of] a divorcee is stringent. [It applies] to all [other Kohanim], yet she is not forbidden from what she was permitted (to Ploni she is a widow) due to the side of her that is divorced. (Her status of a widow to Ploni overrides it, even though this is a leniency). All the more so [on the side of stringency, we should say that before Reuven died,] she is forbidden to what she was permitted (all other men) due to the side of her that is an Eshes Ish (regarding Ploni! We explained this based on MEICHAL HA'MAYIM.)

Answer: (The question assumed that after Reuven died, she is permitted to Ploni, like a widow. This is wrong.) The divorce affected even him. (Perhaps this is like the Bavli (8b) expounds "v'Ishah Gerushah me'Ishah Lo Yikachu" - even if she was divorced only from her husband, she is forbidden to a Kohen, and all the more so here that she was divorced regarding all other men. -PF)

Question: (If so, we can ask oppositely!) A divorcee is a light Isur, yet [after Reuven died,] she is forbidden [to Ploni, to whom she is a widow], due to the side of her that is divorced. Eshes Ish, which is severe, all the more so she should be forbidden [to all men in Reuven's lifetime] due to the side of Eshes Ish in her (regarding Ploni)!

Question #4 (R. Akiva): If he said to her 'you are permitted to every man on condition that you will not marry Ploni', and she married someone else (David), and had children from him, and he died, and then she married Ploni, is it not found that [she was never divorced, and] her children from the other (David) are Mamzerim?!

Note: It seems that we must change the text to say 'on condition that you will not marry'; it seems that KORBAN HA'EDAH had this text. If he said 'except for Ploni', marrying him would not nullify the Get retroactively! The Bavli (83b) says that R. Akiva was unsure if R. Eliezer discusses 'except for', or 'on condition that', and he asked a question according to each version. (PF)

Inference: Death [of David] does not permit what the first (Reuven) forbade.

Note: KORBAN HA'EDAH and PNEI MOSHE say that this is unlike we said above. I see no need to say so. Above we discussed 'except for', and here we discuss 'on condition that...'!

Question (R. Shamai): Do we find that a woman, initially one (David) is not liable for her for Ervah, and at the end (after she married Ploni) he is liable for her for Ervah?!

Answer (R. Mana): What is this like? It is like one who told his wife 'this is your Get on condition that you will have Bi'ah with Ploni.' Initially he is forbidden to have Bi'ah with her. (OHR SOMAYACH Kuntres Zikah 20 - even though retroactively it is a Get, initially he has Bi'ah with an Eshes Ish.) If he transgressed and had Bi'ah, the Get permitted her retroactively. (Likewise, Heter can revert to Isur.)