1) THE CASE OF A ZAKEN MAMREI THROUGH "SHICHECHAH"
QUESTION: The Beraisa (87a) lists the categories of Halachah to which the law of Zaken Mamrei applies. If he argues with a ruling in any of those categories, he can be punished as a Zaken Mamrei. The Gemara gives specific examples of rulings in those categories. In the category of Shichechah, the Gemara gives as an example the argument between Beis Shamai and Beis Hillel. The Mishnah in Pe'ah (6:5) states that when one or two sheaves of grain were forgotten in the field when the other sheaves were collected, they must be left for the poor (as described in Devarim 24:19). When three sheaves were forgotten together, the owner of the field may keep them. Beis Shamai argues that even three forgotten sheaves must be given to the poor; only when four sheaves are forgotten do they belong to the owner of the field.
In what way does this argument apply to a Zaken Mamrei?
RASHI explains that this Halachah applies to a Zaken Mamrei in the follow situation. The Zaken Mamrei sides with the opinion of Beis Shamai and says that three sheaves must be left for the poor, and, after a poor person has taken the three sheaves, the owner of the field takes them away from him and gives them to a woman for Kidushin. According to the Zaken Mamrei's ruling, the woman is not married, because the object that the owner of the field gave to her (the three sheaves) was stolen property. Consequently, if someone else is Mekadesh the woman, and the owner of the field continues to live with her thinking that his Kidushin was valid, he will be sinning with an Eshes Ish (a sin which makes the Zaken Mamrei liable for punishment).
There is a much more basic case that Rashi should mention: the poor person took the sheaves and was Mekadesh a woman with them himself. Why does Rashi need to give an apparently unnecessary step of the owner stealing the sheaves from the poor person and then being Mekadesh a woman with them? (MAHARSHA)
ANSWERS:
(a) The MAHARSHA answers that Rashi's intention is to explain all of the cases so that the Zaken Mamrei's ruling is not in accordance with the Halachic ruling. If the case here was that the poor person was Mekadesh a woman with the sheaves, then in order for the Zaken Mamrei to issue a ruling that would cause a sin to happen he would have to side with the opinion of Beis Hillel and say that the woman is not married to the poor person. Rashi does not want to give a case in which the Zaken Mamrei follows Beis Hillel, as Beis Hillel's opinion is the Halachah.
(b) The SANHEDRI KETANAH explains the intention of Rashi differently. Even if the Zaken Mamrei's ruling is in accordance with the view of Beis Hillel, and the Sanhedrin rules like Beis Shamai, Rashi cannot say that the case in which the Zaken Mamrei would be punished is where the poor person gives the sheaves (which he took unjustly) to a woman for Kidushin. If the poor person would take the sheaves, he would be considered a Ganav (a thief, who steals surreptitiously) and not a Gazlan (a robber, who brazenly burglarizes and takes the possessions of others by force). He would have the status of a Ganav because when he takes the three sheaves there are many other poor people taking other sheaves of Shichechah from the field, and thus his act of theft is not recognizable. The Halachah is that the owner of an object stolen by a Ganav is considered to have given up hope of reclaiming his object ("Ye'ush"), since it is so difficult to find the Ganav. Therefore, even Beis Shamai -- who maintains that the poor person is not permitted to take three sheaves of Shichechah -- will agree that the poor person's Kidushin is valid when he gives these sheaves to a woman, because the owner's Ye'ush makes him the new owner of the sheaves. If, however, the owner wrestles away the sheaves from the poor person, the poor person knows exactly who took his sheaves and does not forfeit his ownership. Hence, the sheaves are still considered to be in the possession of the poor person, and when the owner of the field is Mekadesh a woman with them the Kidushin is not valid, according to the ruling of the Zaken Mamrei. (Y. Montrose)

88b----------------------------------------88b

2) PARENTS MAY EXEMPT THEIR SON FROM BECOMING A BEN SORER U'MOREH
OPINIONS: The Gemara (end of 88a) quotes Rebbi Yoshiyah who says that "Ze'ira, of the great men of Yerushalayim, related three things to me" concerning Halachos that involved an act of pardon. One of those three Halachos is that the parents of a Ben Sorer u'Moreh may forgive their son and thereby exempt him from being punished by Beis Din. Rebbi Yoshiyah relates that his colleagues agreed with this Halachah.
How does such a pardon work to exempt the sinner from punishment? No other Chiyuv Misas Beis Din can be retracted through forgiveness, or even through the repentance of the sinner. Moreover, at what point must the parents forgive their rebellious son? Are they able to pardon him even after the verdict has been passed?
(a) RASHI explains that after the rebellious son received lashes and then committed the offenses that make him a Ben Sorer u'Moreh, his parents still have the right to forgive him as long as they have not yet brought him to Beis Din. This is because the verse states, "His father and mother shall seize him, and they shall bring him out to the elders of his city" (Devarim 21:19), making his conviction dependant upon them. Rashi apparently maintains that if the parents have already brought him to Beis Din, they no longer have the option of forgiving him.
(b) The RAMBAM (Hilchos Mamrim 7:8) states that as long as Beis Din has not sentenced the Ben Sorer u'Moreh to death, the parents still may forgive him. The KESEF MISHNEH explains that they certainly cannot pardon him after his sentencing, because he already has the status of a dead man.
The MISHNEH L'MELECH comments that the Kesef Mishneh does not explain why the parents may forgive the Ben Sorer u'Moreh even after he is brought to Beis Din, before the sentencing. The verse implies that they may not forgive him once they have brought him to Beis Din, as Rashi says. The Mishneh l'Melech explains instead that it is obvious that the parents may forgive their son at any point until the sentencing, and it cannot be inferred from the verse that they may not forgive him once they have brought him to Beis Din. The Yerushalmi (8:6) explicitly states that either parent may forgive the son, and it continues and says, "We might have thought that this applies only until he is brought to trial. He (Rebbi Yoshiyah) therefore teaches that this applies even if he has already been brought to Beis Din, as long as he has not been sentenced." The Yerushalmi clearly supports the ruling of the Rambam and contradicts the view of Rashi.
The CHASAM SOFER (Teshuvos CM 28:3) answers the question from the Yerushalmi on the view of Rashi. There is a principle (see 86a) that witnesses must be able to be made into Edim Zomemim in order for their testimony to be valid. If they cannot be made into Edim Zomemim, then their testimony is not valid. If the parents would be allowed to forgive their son during the trial, then this would make it impossible to make the witnesses into Edim Zomemim. Beis Din would not be able to punish the witnesses with the punishment they tried to inflict upon the defendant, because perhaps the defendant, in the end, might not be punished with that punishment, since his parents might pardon him. The defendant can be convicted only if his parents are not able to pardon him once the trial has begun. Since the witnesses must be able to become Edim Zomemim, Rashi understands that the Gemara rules that the parents may forgive the rebellious son only before they bring him to Beis Din.
The Yerushalmi, however, does not agree with this principle. It maintains that the testimony of witnesses is acceptable even when the witnesses cannot be made into Edim Zomemim. Accordingly, Rashi's explanation of the Gemara is consistent with the view of the Bavli, and it is not contradicted by the Yerushalmi.
Why, then, does the Rambam rule that the parents may forgive their son even during the trial, if that makes it impossible to make the witnesses into Edim Zomemim? The Chasam Sofer explains that the Rambam maintains that this case is similar to the cases mentioned in the beginning of Makos which are exceptions to this principle, wherein Beis Din accepts the testimony of the witnesses even through Beis Din cannot give the witnesses the same punishment they tried to give the defendant.
The NETZIV (in HA'EMEK SHE'EILAH 134:8) gives a different explanation to defend the opinion of Rashi. He proves that the Yerushalmi and Bavli disagree about the first law stated here by Ze'ira. Ze'ira says that a husband may retract a warning that he gave to his wife not to seclude herself with a certain man. This warning, called "Kinuy," is a prerequisite for becoming a Sotah. Since Ze'ira rules that a husband may retract this warning, does this mean that the woman will never be able to be convicted as a Sotah if she secludes herself with the other man? The Netziv explains that according to the Yerushalmi, the warning remains in force. The husband's retraction of the warning merely serves to weaken it so that she does not have to drink the Mei Sotah. The Yerushalmi, he explains, maintains a similar view with regard to the Ben Sorer u'Moreh. Although the parents are able to pardon their son until he is sentenced, the pardon is in force only as long as the parents want it to be in force. If they later decide to bring their son back to Beis Din, they may do so. Accordingly, their pardon during the trial is considered a postponement of the punishment, and not an absolute reprieve (and thus the witnesses are still considered to be witnesses who can become Edim Zomemim, since it is assumed that the Ben Sorer u'Moreh will eventually be punished).
In contrast, the Bavli (according to Rashi) maintains that the husband's retraction of his warning is absolute and his wife never has any laws of a Sotah (and can never become forbidden to her husband), and the Kinuy is totally nullified. Therefore, Rashi learns that the Bavli disagrees with the Yerushalmi in the case of a Ben Sorer u'Moreh as well. When the parents forgive their son, they give him a total reprieve and they may not bring him back to Beis Din. Hence, they must pardon him before the trial begins. (Y. Montrose)