Baba Metzia 7a - Safeik D'oraysa l'chumra

The Shev Shmaitza (1:3) proves from our gemara that safeik d'oraysa must be l'chumra m'doraysa, to the exclusion of the Rambam who holds that m'doraysa one can be meikil and the rabbonon require going l'chumra. The gemara says that the case where safeik bechor can be put into the coral to be counted toward ma'aser b'heima, cannot be speaking about a safeik bechor of a kosher animal. Why? The gemara explains that the torah says יהיה קודש ולא שכבר קדוש, meaning that only things which begin without kedusha can count toward ma'aser b'heima, to the exclusion of a b'chor of a kosher animal which is already kadosh. Now, what makes a safeik b'chor "already kadosh"? Presumably, it is the fact that since it is a safeik, one cannot work with it because safeik d'oraysa l'chumra. From this we see that the torah itself recognizes that fact that a safeik b'chor cannot be worked with and therefore has kedusha status, because safeik d'oraysa is l'chumra on a d'oraysa level. But if safeik d'oraysa was l'kula, then the safeik b'chor would have no kedusha on a d'oryasa level and should not be excluded by the pasuk from ma'aser b'heima.

The steipler (kehilas yakov 8) pushes off the proof of the shmaitza. The question of whether it is forbidden m'doraysa or only d'rabonon to work with a safeik b'chor, does not reflect on the true kedusha status of the b'chor. Although safeik d'oraysa is l'kula, that is just a way that one may conduct themselves in a situation of safeik issur. But, it does not indicate that there is truly no kedusha on the safeik b'chor. Meaning, safeik l'kula is not a method to determine actual status of the animal, it is just a halacha in how to conduct oneself with the safeik b'chor. Therefore, even according to the rambam that safeik is l'kula and the safeik b'chor is permitted to be worked with, the torah still recognizes it as having safeik kedusha and is therefore excluded from the pasuk of יהיה קדש - ולא שכבר קדש. This is a big chiddush in how to look at safeik l'kula and also look at safeik l'chumra - the torah is not being machria that it is considered definite heter or definite issur, rather the torah is merely telling us how to conduct ourselves in a situation of safeik.

Baba Metzia 5b - Lifnei Iver

There is a discussion in the achronim about the issur of lifnei iver. Although the gemara makes it clear that lifnei iver only applies when it is תרי עברי דנהרא - two sides of the river, meaning one is only in violation if without him the person didn't have access to the issur. However, there is a machlokes in a situation where the person had the ability to violate the issur without assistance, but he would not have violated it. The question is when one could have violated an issur without assistance, but would not have - Is provoking one to violate an issur, even when not enabling, a d'oraysa violation of lifnei iver? The Taz (y.d. 148:3) implies that so long as the person could have done it, it is not a violation of lifnei iver to provoke him to do it. However, the Chazon Ish (63:13) disagrees and holds that if you are מכריע חפצו to violate an issur that he could have without you, but would not have, is also a torah violation of lifnei iver.

A proof to the chazon ish can be brought from the gemara in kiddushin 32a where the gemara implies that there is a torah violation of lifnei iver for a father to provoke his son to him him. Although the son could have hit the father without being provoked, he would not have, and therefore the provoking is a violation of lifnei iver (one can argue that it is only d'rabonon).

One can also bring a proof to the chazon ish from our gemara. The gemara says that it would be lifnei iver to give over one's sheep to a Sheppard (if the Sheppard was suspect of grazing the animals on stolen fields). Why is this lifnei iver?  By giving my sheep to the Sheppard I am not enabling him to steal from other peoples fields. The Sheppard could have stolen without my sheep. I am merely provoking him and providing him with a reason to steal. The gemara seems to hold that even though he could have done the aveira without me, since he wouldn't have it is considered lifnei iver (unless here too the gemara means that it is just a d'rabonon violation).

Baba Metzia 4a - הילך

R' Chiya says that included in the case of modeh b'miktzas where the person partially admits and partially denies, is also a case of "hei'lech". Meaning, Reuven claims 100, Shimon responds by denying 50 and admitting on the other 50 saying "hei'lech". R' Chiya holds that shimon is required to take a shavua on the 50 that he denies. R' Sheishes disagrees and holds that hei'lech is patur, because the 50 that he is admitting on is as if it has already been returned to the lender and the entire claim is only on the 50 that is being denied, so it is a case of kofer hakol which does not require a shavuah.

What is "hei'lech"?

Rashi writes - והילך - לא הוצאתים והן שלך בכל מקום שהם

Rashi implies that in order to qualify as hei'lech in a case of a loan, the borrower must say that he didn't spend the money, but if he would have spent the money and is presenting the lender with other money, that would not qualify as hei'lech. The hagahos ahsri understands rashi exactly like this, and therefore holds that if the borrower spent the money and is now replacing it by returning other money, even though we pasken like r' sheishes that hei'lech is patur, the borrower would have to swear because this isn't a case of hei'lech. However, the Bach on the Rosh says that rashi is not coming to define hei'lech, rather he is coming to explain r' chiya who says that even by hei'lech the borrower must swear. Rashi is coming to say that even if the money has never been spent and it is a supercharged hei'ech, r' chiya would still hold that the borrower must swear. But it is entirely possible that Rashi would hold that according to r' sheishes that hei'lech is patur, it would even be patur if the original money was spent so long as now the borrower is presenting the lender with other money in its place.

The Gr"a quotes from the Ran that a case of a loan is always considered as if the money has been spent since it is given to spend, and therefore a loan never qualifies as hei'lech. The only situation of hei'lech is when one gives another something to watch, and then presents him with only part of it at the time he returns it and denies the other part of it. Based on these rishonim, in a case of a loan, even if it hasn't yet been spent the borrower would have to swear.

Baba Metziah 2a - Divide, Stronger man wins, Leave until Eliyahu comes

The gemara has a variety of rulings that we apply to situation where 2 people are fighting over a particular object. When the object is being held by Reuven and Shimon is claiming that it belongs to him, we apply the standard rule of Hamotzi l'chaveiro alav ha'raya (as rashi points out). In a situation where they are both holding on to the object such as our mishnah, we view it as if each is muchzak in half the talis so that we apply the same rule - each one keeps what he is holding, therefore we divide (as tosafos d.h. v'yachloku and the Rosh explain). A shavuah shouldn't even be necessary, but it's purpose is to prevent theives from grabbing their friends clothes and make fraudulent claims (gemara 3a). However, if they are arguing about something that is not in the possession of either one of them, such as the case of a boat where each one is claiming that it belongs to him, Tosafos explains that since there is no muchzak we apply the rule of כל דאלים גבר, meaning that the "stronger one" wins. The Rosh elaborates that this is really a technique that beis din uses to stay out of the situation. Although beis din is required to involve themselves when they see someone taking from someone else, in this case since no one person is a muchzak they are not required to get involved (the rosh also offers some justification as to why this method would likely result in the rightful owner winning).

The mishna considers the two who are holding on to it to both be muchzak in the talis. But, in the second case in the mishna, they are in exactly the same positions physically grabbing on to it, yet we say that Reuven gets 3/4 and Shimon gets 1/4. Why don't we disregard their claims and view their status as being each muchzak in half to split it evenly as we do in the first case? It seems that the status of being muchzak is not a result of their actions of holding it alone, rather it is a combination of their holding it in conjuction with their claims. Meaning, only because they are both claiming it to be fully theirs do we consider them each to be muchzak on half. Therefore, in the second case where both agree that half belongs to Reuven, Reuven is automatically considered a muchzak on 3/4 and Shimon a muchzak on 1/4.

Rashi (2a) and Tosafos (2b) argue what the din will be in a case where 2 people are holding a talis, each claiming that it belongs to him because he wove it himself (unlike the mishna where they are claiming to have found it or purchased it). The difference between this case and the mishna case is that in the case where they are claiming to have woven it, one of them is definitely not telling the truth (whereas in the mishna it is possible that they picked it up together). Rashi holds that in the case where they claim to have woven it, since one of them is definitely a thief, we apply the din of יהא מונח עד שיבא אליהו. However, Tosafos says that we apply the same din as our mishna of dividing with a shavua (the fact that one is a thief will make the shavua even more effective because even a thief is not suspect to swear falsely). The Rosh proves that Tosafos is correct from the gemara 3a which asks why the by מנה שלישי do we say יהא מונח rather than יחלוקו? The gemara says that since the third 100 zuz definitely belongs to either Reuven or Shimon, but definitely doesn't belong to both, we can't divide it. Rather than using the rationale that we don't divide since one of them is definitely cheating (as the gemara says by r' yossi), the gemara implies that even if one of them is definitely cheating we will still divide so long as it is still possible that it belongs to both of them. Therefore, in the case where each one claims to have woven it, where one of them is definitely cheating, we would still divide, since it is possible that they both own it.

Baba Kama 117a - Moser

The gemara illustrates from the story of Rav and Rav Kahana that it is permitted to kill a person who threatens to be moser. The Shulchan Aruch (c.m. 388:10) writes that this applies even nowadays because a moser has status of a rodef since it will lead to physical danger (as the sm"a explains, when the goyim find out he has money they will threaten him physically). The Rama rules that prior to killing him, he should be warned, but if there is no time to warn, or injur him as you would stop a rodef, you can kill him on the spot as r' kahana did (the yam shel shlomo discusses why r' kahana needed to run away to do teshuva if he was permitted to kill the moser. He suggests that either he needed teshuva for paskening in front of his rebbi, or he needed teshuva for endangering his own life). This applies only until the moser actually commits the act, but once he has already reported to the goyim, the shulchan aruch (388:11) rules that it is assur to kill him, just as a rodef can't be killed after taking someones life (unless there is a chance that he will continue). The shach points out that the ri"f seems to disagree with the rambam and shulchan aruch, that even afterwards he can be killed. Even according to the shulchan aruch that once he did the mesira he cannot be murdered, if he was repeatedly moser, the Rama (15) writes that he can be killed through grama. The Shach quotes the teshuvos ha'rosh that included in "grama" would be hiring a hit man to kill him. The maharshal disagrees and holds that hiring a hit man is the equivalent to killing with his own hands which is not allowed unless there is imminent danger of him reporting again. The rationale of the maharshal is that by a goy we say יש שליח לדבר עבירה to be machmir, so it is as if the jew who kills through a non-jewish agent actually committed the murder himself. 

R' akiva eiger refers to a teshuva of the beis yakov (siman 2) who says that even if we accept that a goy can be a shliach for a jew l'chumra, since a goy is also forbidden to kill we should say אין שליח לדבר עבירה so that the act of murder is not attributed to the jew at all? The Beis Yakov explains the opinion of the maharshal based on the tashbetz who says that when it is obvious to the sender that the shliach completely disregards dinei torah, he cannot have a claim of דברי הרב ודברי התלמיד דברי מי שומעין which is the basis for אין שליח לדבר עבירה. Therefore, by a goy and even a yisroel mumar we would say יש שליח לדבר עבירה to consider the act of the aveira as if it were performed by the sender himself (he continues to suggest that the concept of יש שליח לדבר עבירה when the shliach is a goy, only applies when the sender is a jew, but when the sender is also a goy we would say אין שליח לדבר עבירה).

Baba Kama 116b - Claiming that you did it for yourself

Reuven asks Shimon to  purchase a lottery ticket for him, Shimon purchases the ticket and wins. Can Shimon claim that he purchased it for himself, or does the money belong to Reuven?

The Machaneh Ephraim (Shluchin 19) quotes a machlokes mentioned in the Tur (c.m. 184). The Ramah holds that Shimon was serving as Reuven's agent and is not believed to say he purchased it for himself. But the Rashba in a teshuva writes that when 2 people agree that they will split profits of their business equally, on partner is not believed to say that he had intended to break the partnership and all the profits that he earned are his own, unless there was a formal declaration made in the presence of witnesses that he broke the partnership. The Rashba proves this from our gemara where the worker saved the possessions of his employer, and so long as he didn't retract on his status as a worker, we assume that he was doing it on behalf of the employer and not on behalf of himself. The machaneh ephraim understands from the rashbah that who bases his ruling on our gemara that refers specifically to a worker, that only a paid worker is not able to break his employment agreement without a formal declaration. But this implies that one who is not a paid worker can claim at any moment that he retracted from his original commitment. Based on this, the Ramah would say that the lottery ticket belongs to Reuven, but the Rashba will say that Shimon is believed to say that he retracted and keep the ticket for himself.

Baba Kama 115b - Bal Tashchis : בל תשחית

The gemara says that water that has been left uncovered and their is concern that snake venom may be inside, one cannot give the water to an animal. Rashi explains that the rationale is that we are concerned that one may shecht the animal and it will be dangerous to the person who eats from this animal. Tosafos points out that rashi's approach would only apply to a kosher animal, but in truth this din should apply to a non-kosher animal as well because there is a violation of ba'al tashchis to kill the animal for no reason at all. Tosafos proves this from a gemara in avoda zara 30b that it is only permitted to feed it to a cat (snake eater) which will not be damaged by the venom, which implies that it would be assur to feed it to a non-kosher animal which will be damaged by the venom. From Tosafos we see an interesting point regarding ba'al tashchis. Usually we refer to something as wasteful because it has a function to serve a human and it is being wasted. But in a case where the object provides no direct benefit to a human being one can argue that it is permitted to waste it without any violation of ba'al tashchis. Tosafos says that this is not true, because even a non-kosher animal similar to a cat that is not designated to assist people in carrying loads or plowing a field cannot be killed for no reason and would constitute a violation of ba'al tashchis.

Baba Kama 114b - מסיח לפי תומו באיסור דאורייתא

The gemara concludes that a woman or child who don't have believability as an עד אחד נאמן באיסורין are nonetheless believed מסיח לפי תומו by something which is only d'rabonon (such as the bees nesting in someone elses yard, they are believed to say where it came from since the entire kinyan on these type of things is only d'rabonon. But by an issur d'oraysa we wouldn't believe a woman or child and certainly not a goy who is מסיח לפי תומו, with the exception of eidus isha that her husband died and by shevuya where chazal were especially lenient.

The Shulchan Aruch (98:1) rules that a goy is believed מסיח לפי תומו to say that he doesn't taste the issur that fell into kosher food, to be matir the food. The Shach and Taz both ask that the concept of מין בשאינו מינו בנותן טעם, that when food falls into a pot that has a different type of food, there is an issur d'oraysa to eat from the pot so long as the issur can be tasted (which in the absence of believing the goy we would assume that the taste in only nullified in 60 times as much). How can we believe a goy on an issur d'oraysa?

The Shach at first suggests that when there is a chezkas issur we don't believe a goy on an issur d'oraysa but when there isn't any chezkas issur we would believe a goy even on an issur d'oraysa. He then asks that if this is true the gemara should have no question from teruma and shevuya as to why we believe מסיח לפי תומו since there isn't any chezkas issur. Therefore the Shach concludes that since after the goy tells us that he doesn't taste the issur we will be tasting it and be able to call his bluff, he is more careful not to lie, so we can trust him. But in a situation where we won't be able to call his bluff we don't trust a goy even מסיח לפי תומו on an issur d'oraysa even if there isn't any chezkas issur.

The Taz offers an alternate approach. The din that a goy is not believed מסיח לפי תומו on an issur d'oraysa only applies to situations that require eidus, but in the realm of issur v'heter which doesn't require a real eidus, we can trust a goy מסיח לפי תומו. The Chavos Da'as (98:1) explains that the Taz doesn't mean to say that whenever an individual witness is believed it doesn't qualify as eidus, and therefore a goy is believed מסיח לפי תומו even by an issur d'oraysa. Because if that were true the gemara should not have any question from teruma and shevuya as to why מסיח לפי תומו since by those cases an individual witness is believed, so מסיח לפי תומו should also be believed. Rather the Taz acknowledges that even cases where an eid echad is believed would sometimes qualify as a real "eidus" and מסיח לפי תומו would not work on an issur d'oraysa. The litmus test as to whether something requires real "eidus" is whether or not there needs to be a haggada in beis din. Both the case of a kohen being mutar b'teruma and the case of shevuya require a hagadda in beis din therefore מסיח לפי תומו is not believed. But by issur v'heter which doesn't require a haggada in beis din,a goy מסיח לפי תומו is believed even by an issur d'oraysa.

Baba Kama 113a - Davar Sh'eino Miskavein / P'sik Reisha

The gemara quotes a machlokes whether one is allowed to wear shatnez when they are not intending to benefit from it (such as wearing it so that it looks like a personal garment that is not for sale and thereby tax exempt). The gemara says that this is the machlokes that we find all over shas between R' Shimon and R' Yehuda whether a דבר שאינו מתכוין is mutar or assur. The major question is that R' Shimon is only matir a דבר שאינו מתכוין when it is not a p'sik reisha, meaning that the issur may or may not be violated, but in a situation where the issur is definitely being violated, the lack of intent will not permit it. Tosafos (Shabbos 29b) says that it is speaking about a situation that it is not a p'sik reisha because the person is wearing other clothes that protect him, and therefore it is only a safeik whether the shatnez garment will also be providing protection. However, the Ran in chulin (32a b'dapei ha'rif) is mechadesh - דלענין הנאה ודאי אע"ג דהוי פסיק רישיה שריא דהא אמרינן התם מוכרי כסות וכרין כדרכן ובלבד שלא יכוונו בחה מפני החמה ובגשמים מפני הגשמים וכו' דכיון דלא מיכוין לה לא חשבינן לה מידי

The Ran holds that issurei hana'ah are different than other issurim in that pleasure can only be appreciated and qualified as a benefit when there is intent. In the absence of intent, it doesn't qualify as hana'ah. That is why R' shimon is matir by issurei hana'ah even when it is a p'sik reisha. 

The Ran in Shabbos (41a b'dapei harif) explains the rationale to be matir even when there is an inevitable benefit somewhat differently - לפי שלא אסרה תורה אלא מלבוש שסתמו להנאה אבל כל שאין לו הנאה ממנו אינו מלבוש אלא משוי בעלמא

Here the Ran limits his chiddush specifically to the issur of shatnez. Although other forms of issur hana'ah may very well include acts of hana'ah even when there is no intent, the issur of shatnez is different. The very nature of the issur is to assur the "wearing" of shatnez which by definition requires intent to benefit from the clothes.

The difficulty with the approach of the Ran is that the chiddush is really a chiddush in the specific issur of shatnez (Ran in Shabbos) or the concept of "hana'ah" (Ran in chulin), but has nothing to do with the general rule of דבר שאינו מתכוין being mutar or assur. Meaning, even if דבר שאינו מתכוין is normally assur, one can still hold that hana'ah requires intent, or the issur shatnez requires intent. So, why does the gemara always connect this to the very global machlokes of R' Yehuda and R' Shimon about דבר שאינו מתכוין?

Baba Kama 110 - Kohen Appointing Shliach to Eat Kodshim

The gemara questions what is the case where a zaken or choleh appoints someone else to do the avoda and eat the korbanos for him. If he is unable to do the avodah and eat, how can he appoint a shliach. The gemara concludes that he is able to do avoda and eat b'dochek, therefore avoda b'dochek which qualifies as avoda he can appoint a shliach for, but eating b'dochek which qualifies as over eating which is assur by kodshim he can't appoint a shliach for. The gemara seems to assume that the kohen who belongs to the mishmar must appoint a shliach to eat kodshim for him. The maharatz chiyus associates this with the gemara in nazir 12a that says that one must be able to do something himself in order to have the authority to appoint a shliach to do it for him. Based on this the Maharatz chiyus asks, the mitzvah of eating kodshim is not a mitzvah on the "gavra" rather it is a mitzvah that the "cheftzah" must be consumed (the chasam sofer and beis halevi discuss this issue in contrast to korban pesach). This is clear even from the gemara's assumption that the elderly kohen of the mishmar can appoint another kohen as his shliach to eat the kodshim for him, which certainly cannot be done by the mitzvah to eat matza because this mitzvah is not an obligation on the individual. But since it is just a mitzvah on the cheftzah that kodshim should be eaten, why is shlichus necessary to allow another kohen to eat from the korban?

It seems to me that this sugya is not at all connected to the inyan of shlichus. The term shlichus over here doesn't refer to the concept of appointing another kohen to stand in his place, rather it refers to the ownership of the rights to eat and the ability to pass on those rights to someone else. The gemara is not using the rule of nazir 12a that one must be able to do it himself in order to appoint a shliach, it is instead using the obvious rationale that one cannot gift to someone else something that he doesn't own. The ownership of the mishmar in kodshim is only when the individual is able to participate in that activity, whether it is avoda or eating, in which case he can offer those rights to someone else. But when he is unable to do avoda or eat, he is not considered someone who has ba'alus over that activity and therefore cannot pass it on to anyone else. Therefore, the gemara concludes that the case must be that he can do avoda b'dochek, so he can gift that right to a friend who is a kohen and not in that mishmar, but since his eating b'dochek would not make him eligible to eat kodshim, he doesn't own that right and cannot pass it on.

Baba Kama 100a - Goreim l'mamon vs. Grama vs. Garmi

The gemara established that according to R' Meir one is chayev even for indirectly causing a loss to someone, such as not rebuilding the fence between a vineyard and a field so that the vines cause issur to the field. The gemara 98b clearly makes a distinction between the rule of R' Shimon דדבר הגורם לממון כממון דמי, and the rule of R' Meir דדאין דינא דגרמי. In the particular case of the gemara where one burns his friends contract causing him a loss, the gemara says that R' Shimon's goreim l'mamon would not apply since the contract itself has no inherent value. Yet, the gemara concludes that one would be obligated through dina d'garmi. The gemara seems to imply that it is more likely to be chayev using dina d'garmi more than using the concept of goreim l'mamon, therefore whenever R' Shimon would hold that you are chayev, R' Meir would certainly hold that you are chayev. However, Tosafos 71b (d.h. v'savar) explains that R' Meir's din of garmi would only apply to cases where the money has value to everyone in the world, but something which only has value to a particular individual would not be included in the concept of garmi, but would be in the concept of goreim l'mamon. For example, chometz after pesach which is assur b'hana'ah to the entire world and only has value to the ganav (98b), even though R' Shimon would hold that one is chayev to the ganav for destroying it after pesach since to him it is worth something (returning to the owner and declaring הרי שלך לפניך), R' Meir would hold that garmi doesn't apply.

R' Shimon's concept of goreim l'mamon is a chiddush in the type of object that was destroyed [it must have inherent value to the exclusion of a contract, but doesn't need to have value for the whole world], but he would require the destruction to be a direct action of the mazik. Whereas R' Meir's concept of garmi is a chiddush in the action done by the mazik that it need not be a direct act of damage, but the object must have value for everyone in the world. In the case of the contract, if we were to be mechayev using the concept of goreim l'mamon (if not for the fact that it has not inherent value), we would consider the contract to be valued at whatever the lender can collect for it, so that when it is damaged the chiyuv is for damaging the paper of the contract which is regarded as money. But, when we are mechayev using garmi, the chiyuv is not for the destruction of the contract, rather it is for causing the lender to be unable to collect the debt owed to him.

Regarding garmi and grama, we generally assume that grama is patur, but garmi is chayev. Although the ketzos (386:2) explains that according to the rambam every case of grama is chayev according to R' meir based on garmi, most authorities assume that even according to R' Meir there are some cases which qualify as grama and others which qualify as garmi. An example would be the case in the gemara 99a where one knocks some one's coin into the sea, into clear water where a diver can retreive it (machlokes rashi and tosafos if you need both, or the definition of clear water is that a diver can retreive it). The Ketzos (386:10) quotes from the hagahos mordechai that garmi is when one indirectly causes a loss to some one's money, but when one doesn't cause a loss to some one's money or object, rather he causes someone to be forced to incur an expense to retreive his money or object i.e. hiring a diver to retrieve his coin, even R' meir would hold that the mazik is patur.

Baba Kama 98b - Chometz after pesach: Did the Chachamim k'nas inheritors?

The Nodeh B'yehuda (o.c. 20) has a long and elaborate teshuva discussing a situation where a father died after chatzos on erev pesach and had chometz in his possesion. After proving that the children do not inherit this chometz and therefore have no obligation to dispose of it (since it is already assur b'hana'ah so it is not "owned" by the father to pass it on to the children), he discusses whether the children are able to benefit from this chometz after pesach. At first he makes this dependent on whether there is a violation of בל יראה ובל ימצא after chatzos on erev pesach, or only at nightfall. Presumably since the father owned the chometz after chatzos until he died, the chometz would be assur if the father was in violation of בל יראה ובל ימצא. Although most poskim assume that the issur of בל יראה ובל ימצא only begins at night, the nodeh b'yehuda proves that the opinion of the Rambam is that it applies already after chatzos on ereve pesach (this also seems to be the opinion of rashi in pesachi 4a). Even the Ra'avad who disagrees with the rambam would hold that chometz is mutar to derive benefit from (shitas r' shimon that lifnei zemano it is mutar b'hana'ah) until pesach begins, so that the children inherit it and they themselves would be in violation of בל יראה ובל ימצא at nightfall when pesach begins.

But, he then says a big chiddush to be matir the chometz after pesach in this case. He introduces this by pointing to many gemara that address the issue of whether a penalty implemented on the father would apply to his children who inherit from him - what is the din by chometz she'avar alav ha'pesach by the father, is the penalty imposed on the children?

The mishna says that a gazlan can return to a nigzal chometz after pesach (even though it is assur b'hana'ah). The gemara proves from this that by issur hana'ah one can say הרי שלך לפניך. Simply this indicates that it is assur to the nigzal, otherwise there would be no proof to other issur hana'ah (which is assur to everyone). However, the N.B. explains that the chometz is really only assur to the gazlan but mutar to the nigzal. His assumption is that really we are only interested in imposing a penalty on the violater of the issur, but normally we are forced to make it assur to everyone to ensure that the violater will not benefit from the issur by the ability to pass it off to someone else. We can assume that when the violater will not benefit by the ability to pass it off to someone else, the rabbonon wouldn't impose their penalty. Based on this, he explains that the logic of the gemara is that if by issur hana'ah one cannot say הרי שלך לפניך, then the gazlan would benefit by it being mutar to the nigzal because the heter to the nigzal would allow him to return it, which is not the case by other issurei hana'ah. But if by issur hana'ah one can always say הרי שלך לפניך, regardless of whether it would be mutar to the nigzal or assur to the nigzal, the gazlan would be able to return it. Therefore, there is no reason for the chachamim impose their penalty on the nigzal. Normally, they would assur it to everyone to avoid the person who violated the issur from being able to benefit, but here there is no rationale to assur it to the nigzal since even if it is assur to the nigzal (such as other issurei hana'ah) the gazlan can benefit from it by returning it to the nigzal.

Based on this chiddush that if one steals chometz and returns it after pesach, the nigzal can benefit from the chometz and even eat it. From this the N.B. makes a jump and says that if chazal didn't impose a penalty on the nigzal, so too when one owns chometz on pesach and dies, there wouldn't be a penalty imposed on his inheritors. The N.B. suggests a distinction. The chometz that was in the hands of the gazlan never became assur to the nigzal since there was never any rationale to assur it on the nigzal, but the chometz that became assur to everyone in the lifetime of the father, would remain assur even upon the fathers death so that the inheritors cannot benefit from it (which is meduayk in the language of the Rambam - חו"מ א:ד - חמץ שעבר עליו הפסח אסור בהנאה לעולם.

For brevity purposes i am switching to hebrew:

והטעם שהחמירו בחמץ יותר  משאר קנסות שקנסו לאסור אף על היורשים, משום דלא נקרא שם האיסור על גוף הדבר כגון במלאכת חוה"מ דלא שייך שם איסור על המלאכה, אבל חמץ אחר הפסח חל שם איסור על החמץ ואינו חוזר להיות מותר במיתת העובר עבירה. אכן, אף שהעלה הנוב"י שבחמץ בפסח קנסו בנו אחריו, מ"מ ס"ל דדין הראשון גבי גזלן שגזל חמץ לפני הפסח ועבר עליו הפסח שאומר לנגזל הרי שלך לפניך, וחידש שמותר בהנאה להנגזל "שהוא אמת וברור". ובסוף התשובה התיר אף להיורשין כל שמת האב קודם הפסח או אפילו בתוך הפסח, שהרי כל הסברא לאסור להיורשין משום דכבר חל הקנס על האב, ומסתברא דלא חל הקנס בתוך הפסח בזמן שהוא אסור בהנאה מדאורייתא, אלא שבכלות הפסח וחוזר מה"ת להיות מותר חל הקנס, וכל שחל רגע אחד לעולם לא פקע. לכן כשמת בתוך הפסח ולעולם לא חל הקנס מותר להיורשין ליהנות ממנו אחר הפסח, אבל כשמת האב שעבר בב"י וב"י רגע אחר הפסח, כבר חל עליו הקנס ואסור להיורשין ליהנות ממנו. עכת"ד הנוב"י

Baba Kama 95a - Takanas Hashavim

The gemara says that in the days of rebbi they made a takanas hashavim that if one stole or took money as interest, he does not have to pay it back (the beis din is not even allowed to allow the nigzal to receive it), so that people will not be discouraged from doing teshuva. The gemara limits this to gezeila that is no longer here to return, but when the object is here he must return it. Tosafos continues to limit this takana even more by saying one of the following: a. it only applied during the time period of rebbi, not before or after. b. it only applies to a professional thief who would more easily be discouraged from teshuva. c. it only applies when he is coming forward to repent, not when he is caught and forced to return (tosafos rejects this approach).

However, the gemara mentions a more mild takanas hashavim that is paskened in the poskim. When one steals a beam and builds it in his house, technically he should be required to break down the entire structure to return the beam. However, chazal made a takanas hashavim to allow him to return the cash value of the beam rather than the actual beam (rashi explains that the takana of rebbi doesn't cover this case since the beam is still here and can be returned, that is why this takana doesn't exempt the thief completely).

In Shulchan Aruch (c.m. 360) we pasken that the beam doesn't have to be returned and it is sufficient to return money. However, the rama writes that if one were to steal property and construct a house on that property, we would not make a takanas hashavim allowing him to pay the cash value of the property. When it comes to theft of property there was not takanas hashavim. Why?

The sm"a (360:6) writes: דלא עשו תקנת השבים בקרקע דכיון דהוא דבר קבוע ועומד הו"ל למידע דשל הנגזל הוא ולא הו"ל לקנותו

This implies that the takanas hashavim was really only for one who purchases stolen goods without realizing that they were stolen. This would not apply to property since everyone knows to who it belongs. The approach of the sm"a is a big chiddush because we never find that the takanas hashavim is limited to one who used stolen goods accidentally. The be'er heitev writes over the sm"a and replaces the word "לקנותו" with the word לבנותו (nesivos also makes this correction), but the magiah on the be'er heitev is still not sure what that really accomplishes.

The Taz seems to understand that the takanas hashavim was not only for the benefit of the gazlan to do teshuva but also for the nigzal. It is very likely that without the takana, the stolen item will never be returned and will eventually rot away. They made it easier for the thief to do teshuva to protect the nigzal and make sure that he is reimbursed. Property which will never disappear, and eventually be returned to the rightful owner when Hashem decides to weaken the hand of the thief, they didn't need a takana to protect the nigzal. The Pischei Teshuva quotes the levush who has a similar approach, that property which cannot be hidden and will eventually be returned, does not require a takana to protect the nigzal. The difficulty with this approach is that the takanas hashavim of rebbi was purely for the benefit of the gazlan to encourage him to do teshuva without any concern for the nigzal. Presumably, this lower level takana which makes the gazlan at least return cash, is also for the benefit of the gazlan, but not instituted to benefit the nigzal, therefore it should apply to property as well.

A completely seperate issue - R' Akiva Eiger refers to the chavos yair who discusses a situation of a goy who steals from a jew and then converts, must he return stolen goods that he has. He quotes Tosafos in sanhedrin 71a who asks why a goy who commits murder and then converts is still chayev misah, we should say that he is כקטן שנולד דמי, an entirely new person? Tosafos answers that b'dinei shamayim he is like a new person with a clean slate, but in dinei adam he remains responsible for the acts he commited as a goy. Therefore, he is obligated to return an item that he stole as a goy. Basically, the idea of גר שנתגייר כקטן שנולד דמי, is the equivalent of a jew doing teshuva, but that will not remove from his punishments from beis din or returning stolen goods. But, the question can still be asked whether there is a takanas hashavim for such a situation - For example, a goy stole a beam and built a house, he then converted, would there be a takanas hashavim to allow him to pay cash rather than knock down the house?