Pesachim 36a: Rabbi Yehoshua said to his sons, “On the first day of Pesach, do not mix milk into the matza. For the rest of Pesach, mix milk into the matza.” But didn’t we learn in a Baraisa that it is forbidden to mix milk into bread, and if one did so, the bread is forbidden to eat, lest one come to eat it with meat? – Here they made the matzo in the shape of an ox [so that it’s distinguishable from regular bread].

פסחים לו ע”א: כדאמר להו רבי יהושע לבניה: יומא קמא לא תלושו לי בחלבא, מכאן ואילך ־ לושו לי בחלבא. והתניא: אין לשין את העיסה בחלב, ואם לש ־ כל הפת אסורה, מפני הרגל עבירהִ וכו’ כדאמר רבינא: כעין תורא שרי, הכא נמי: כעין תורא.

Once, a company began to sell milchige bread with a reliable hechsher. Rabbi Moshe Heinemann asked the rav hamachshir how he could have permitted this. The rav responded that his rebbe, a well-known talmid chacham, said that just as the Gemara permits milchige bread when made with a distinct size or shape, the same applies if the word “dairy” is printed on the package. This would be sufficient to warn people not to eat this bread with meat. “And,” he added, “I discussed this with Rav Moshe Feinstein, and he agreed.”  

Now, as long as this rav was following his rebbe, Rabbi Heinemann couldn’t have any complaints against him. But when he added the part about Reb Moshe, Rabbi Heinemann suspected that something wasn’t right. Did Reb Moshe really issue such a lenient ruling? The Shulchan Aruch only mentions that changing the shape of the bread itself helps – not writing it on a separate piece of paper.

Rav Heinemann went and asked Reb Moshe if he had really said that. Reb Moshe replied, “No, I never said that, but I know how the mistake came about. The rav hamachshir had asked Reb Moshe if writing the word “dairy” on the wrapper would be sufficient, and I replied that it wouldn’t help because the bread is not served with the wrapper. The rav hamachshir must have understood from what I said that if you serve the bread with the wrapper, then it would be permitted. However, I was just saying that even according to his logic, it would not help to write that because people don’t serve bread with the wrapper. I myself hold that even if you serve it with the wrapper, it is forbidden.”  Rabbi Heinemann went back and told this to the rav hamachshir, who promptly removed his hechsher.

Source: Kuntres Mah Nomar, Hilchos Kashrus p. 89

The OU gives a hechsher on Thomas’s English muffins, which contain milk. Their original reasoning was that the distinctive shape of the muffins is commonly associated with dairy. However, later, as pareve English muffins have become common, that reason no longer applied. Still, the OU continues to certify the muffins because the amount of milk is less than one sixtieth and is thus nullified.

Source: oukosher.org

Rabbi Yisroel Reisman mentioned another rationale: since the company is not Jewish, no Jew would eat the muffins without looking at the hechsher. And since the hechsher says that it has milk in it (OU-D), that’s sufficient. Thus it’s not necessarily similar to the story above with Reb Moshe: there, the company may have been a well-known Orthodox Jewish bakery, such that people might eat the product without examining the hechsher.  

Source: Rabbi Reisman’s shiur on Yoreh Deah 97.

Pesachim 116a: Rabban Gamliel used to say, “Whoever did not say these three things on Pesach did not fulfill his obligation.”

פסחים קטז ע”א: רבן גמליאל היה אומר כל שלא אמר שלשה דברים אלו בפסח לא יצא ידי חובתו.

Rabbi Joseph B. Soloveitchik was once in Berlin on Shabbos Hagadol, and he heard a German rabbi speak. “The Gemara says,” said the rabbi, “that if Persians forced a man to eat matzah, he fulfilled his obligation (Rosh Hashanah 28a), although he surely did not recite the Hagadah. How is this consistent with Rabban Gamliel’s famous statement: Anyone who did not say these three things on Pesach did not fulfill his obligation: pesach matzah and maror?” The rabbi spoke for a long time about this question. After the speech, Rav Soloveitchik said to him, “You have erred. Rabban Gamliel means he did not fulfill his obligation of telling about the Exodus, but certainly he has fulfilled the mitzvah of matzah.”

The rabbi did not have a ready reply, but the next morning in shul he showed Rav Soloveitchik the comment of the Maharsha on Rabban Gamliel’s statement:

לא מצינו בשאר מצות דבעיא שיאמר בהן על שם מה, דסגי להו בברכה על המצוה, אבל טעם הענין הוא מפורש ברפ”ק דזבחים דכל הזבחים שנזבחו שלא לשמן כשרין חוץ מן הפסח וחטאת דפסולין שלא לשמן וטעם הענין מפורש שם דלפי פגמם ורחקם מן הקדושה בעי טפי קירוב לקדושה דהיינו זביחה לשמה וע”כ אר”ג דגם אכילת הבעלים יהיה מפורש לשמה לקרב אל הקדושה.

“We don’t find regarding other mitzvos that one must say out loud why he is doing them. It’s usually enough just to make a bracha on the mitzvah. But the reason for this is explained in the first chapter of Zevachim. All offerings that were slaughtered with the wrong type of offering in mind are kosher, except for the Pesach and the Chatas. Because they are far from holiness, they require one to slaughter them with the right purpose in mind to bring them closer to holiness. And that is why Rabban Gamliel said that even the eating of the offering must be done with the right purpose in mind.

“An Acharon,” replied Rav Soloveitchik, “cannot say something unless there is a source for it in the Rishonim. In this case, the source for the Maharsha is a Ramban in Milchamos, at the beginning of Berachos, who says:

וזו היא ששנו בברייתא במס’ יומא הקורא עם אנשי משמר לא יצא ידי חובתו לפי שמקדימין וקורין קודם לזמן הזה… והיאך אפשר שהיו אנשי משמר ואנשי מעמד מבטלין מצות ק”ש ואמת ויציב דאורייתא לגמרי…אלא ודאי מאי לא יצא ידי חובתו שלא קיים מצוה כהלכה שאלו מקדימין וקורין קודם שיכיר בין תכלת ללבן… ושנינו כיוצא בה כל שלא אמר ג’ דברים אלו בפסח לא יצא ידי חובתו ולא שיהא צריך לחזור ולאכול פסח מצה ומרור.

The Gemara (Yuma 37b) says that one who says Shema with the kohanim of the mishmar does not fulfill his obligation, because they say it too early. Now, how is it possible that the kohanim did not keep the mitzvah of saying Shema, and Emes Veyatziv which is D’oraisa? Rather, it means that he fulfills his obligation, but not in the best way. As another example of this, Rabban Gamliel says that anyone who did not say these three things on Pesach did not fulfill his obligation, but he does not have to eat the pesach, matza and maror over again.

“So,” Rav Soloveitchik concluded, “that explains why if the Persians forced a Jew to eat matza, he fulfilled his obligation.”

Source: Mr. Stern from the Mirrer Minyan of Borough Park

[It’s interesting that the Ramban is essentially understanding Rabban Gamliel the way the rabbi in Berlin understood him: that the recital of the three things is part of the mitzvos of eating pesach, matza and maror. The only difference is that the Ramban says that you do fulfill your obligation, albeit not in the best way.

Rav Soloveitchik’s original response, that Rabban Gamliel is talking about the mitzvah of telling about the Exodus, is based on the Rambam (Hilchos Chometz Umatzah 7:5), who brings Rabban Gamliel in the middle of his chapter on telling the story of the Exodus, and concludes, “And all these things are what are called Hagadah.”]

Pesachim 4a: Rav’s father was Rabbi Chiya’s brother, and his mother was Rabbi Chiya’s sister. When Rav came to visit Eretz Yisroel, Rabbi Chiya asked him, “Is Ayvo alive?” Rav said, “What about Ima?” So Rabbi Chiya asked, “Is Ima alive?” Rav said, “What about Ayvo?” Rabbi Chiya then said to his servant, “Take off my shoes…”

Yoreh Deah 402:12: If someone’s relative died and he does not know about it, there is no obligation to tell him, even if the deceased is his father or mother. And regarding this it says, “One who brings bad news is a fool.” And it is permitted to invite him to an engagement party, a wedding or any simcha, since he does not know. However, if he asks explicitly, one must not lie and say, “He is alive,” as the Torah says, “Keep far from falsehood.” Rema: Still, when the deceased left a son, it is customary to tell him so that he should say Kaddish. But for daughters, there is no custom to tell them at all.

פסחים ד ע”א רב בר אחוה דרבי חייא ובר אחתיה. כי סליק להתם אמר ליה: אייבו קיים? אמר ליה: אימא קיימת, אמר ליה: אימא קיימת? אמר ליה: אייבו קיים. אמר ליה לשמעיה: חלוץ לי מנעלי וכו’

יו”ד ת”ב,יב: מי שמת לו מת ולא נודע לו אינו חובה שיאמרו לו ואפילו באביו ואמו ועל זה נאמר מוציא דבה הוא כסיל ומותר להזמינו לסעודת אירוסין ונישואין וכל שמחה כיון שאינו יודע מיהו אם שואל עליו אין לו לשקר ולומר חי הוא שנאמר מדבר שקר תרחק: הגה ומ״מ בבנים זכרים נהגו להודיע כדי שיאמר קדיש אבל בבנות אין מנהג כלל להודיעם (מהרי״ו סי׳ י״ג).

It was June 15, 1987, Dovid Kaufman’s wedding day, and preparations were in full swing. The Kaufmans together with the kallah’s family, the Steinbergs, had rented out the biggest hall in town, Brightstone Manor, and the cooks were busy preparing the reception and wedding meal for 500 guests. The women of the family were at the hall from the middle of the day, getting their makeup and hair done. Of course, Dovid’s mother Chana knew that her mother could not attend. The last time Chana had visited her at the nursing home, she had been unable to get out of bed. Chana promised to visit her the day after the wedding and tell her all about it.

At 4 PM, the phone rang in the Kaufman home. Dovid’s brother Nachman picked it up. It was a staff member at the nursing home. “We’ve been trying to reach Chana Kaufman,” they said. “She must come right away – her mother passed away!” Absorbing the shock of the news, Nachman thought quickly. “My mother is out now. Don’t worry, I will tell her.”

After hanging up, he thought: what if my mother becomes a mourner right now? Will she be able to take part in Dovid’s wedding? Can she walk him down? How will she be feeling? Is it even right to tell her at a time like this? He decided to ask his rosh yeshiva, who was an experienced posek. He would surely know what to do.

“Don’t tell her,” said the rosh yeshiva. “There is no obligation to tell her and ruin her simcha. She will find out on her own tomorrow. And make sure that if any of the other wedding guests are aware, they do not tell her either.”

Source: Rabbi Yisroel Reisman, tape R-14 (All names are fictitious because the story was told without names)

Pesachim 7a: Rav Yehuda said: Before the search for chometz, one must make a bracha.

Rosh: “Some say that one should not speak until he finishes the bedikah, and some even say that if one did speak about matters unrelated to the bedikah, he must repeat the bracha. But I disagree. True, one should not speak between the bracha and starting the bedikah, but once he has started, speaking is not a hefsek, just as one may speak while sitting in a succah or during a meal and does not have to repeat the bracha on the succah or the hamotzi. Still, it is best not to talk about unrelated matters until finishing the entire bedikah, so that he should concentrate on checking every room and place where chometz is brought.” The Shulchan Aruch 432:1 rules in accordance with the Rosh.

פסחים ז ע”א: אמר רב יהודה: הבודק צריך שיברך.

הרא”ש: ויש אומרים שאין לבודק לדבר עד שיגמור הבדיקה ויש מוסיפין עוד יותר ואומרים שאם סח בדברים דעלמא שלא מעין הבדיקה שצריך לחזור ולברך וכל זה אין נראה לי אלא שיש ליזהר שלא יסיח בין ברכה לתחלת הבדיקה ואחר שהתחיל לא הויא שיחה הפסק מידי דהוה אישיבת סוכה וכאדם המדבר בתוך סעודתו דלא הויא שיחה הפסק להצריך לחזור ולברך על הסוכה וברכת המוציא… ומיהו לכתחילה טוב ליזהר שלא יעסוק בשיחה בטילה עד שיגמור כל הבדיקה כולה כדי שישים אל לבו לבדוק בחדרים ובעליות ובכל מקום שמכניסין בו חמץ.

One of the things that resulted from Rav Chaim Kanievsky’s long bedikas chometz was a complete booklet on the topic of bedikas chometz. Rav Chaim zt”l was accustomed not to speak during the bedikah, beginning from the bracha until the end – except for matters related to the search. Even if people were asking for a bracha, he would not answer with words, but only nodded his head.

One of the relatives who assisted Rav Chaim zt”l with bedikas chometz each year thought of an idea. Several days before Pesach he prepared questions about the laws of bedikas chometz. During the time of the bedikah, he came with pages of questions, and Rav Chaim zt”l answered all the questions, since they were related to the search. However, he would not answer shaalos on other topics. In this way, by the end of bedikas chometz, which took many long hours, he accumulated hundreds of answers from Rav Chaim which encompassed all the laws of the bedikah, enough to fill a complete sefer.

Source: Derech Emunah Bacharti, p. 3

[The Rosh does not say who this authority was who held that if one speaks, the bracha must be repeated. And the Rosh’s argument against this seems very convincing. After all, when doing the same mitzvah, such as succah, for an extended period of time, one need not be silent for the whole time. Why should bedikah be any different?

The answer may lie in the Rema in the following s’if, 432:2. The Rema quotes the Mahari Brin (Rabbi Yisroel Bruna) who held that before the bedikah, pieces of chometz should be put out so that the searcher will find them and his bracha will not be in vain. The Rema then disagrees and quotes with approval the Kol Bo, who says that the bracha is not in vain because when a person says על ביעור חמץ – “on the destruction of chometz,” he has in mind to destroy it if he finds it.

It seems that this dispute is about whether the bracha goes on the searching itself (i.e. Chazal enacted that we must search for chometz, so whether we find any or not, we are fulfilling the mitzvah), or on the actual finding and destruction of chometz.

If so, according to the opinion of the Mahari Brin that the mitzvah is to actually find chometz, if one began the bedikah but did not yet find anything, he has not started the mitzvah and thus would not be allowed to interrupt with speaking. One who spoke before finding the first piece of bread would have to repeat the bracha. This would be the meaning of the opinion quoted by the Rosh. (Although the Rosh lived before the Mahari Brin, we can assume that the authority he quoted held the same position as the Mahari Brin.)    

The Taz, commenting on the Rema about putting out ten pieces, offers a different reason why the bracha is not in vain even if ten pieces were not placed and no chometz was found: because the bracha refers to the burning of the chometz in the morning. The difficulty with the Taz is: what if no ten pieces were placed, no chometz was found during the search, and the person’s bracha therefore goes only on his burning in the morning? Then it should come out that he would not be allowed to speak from the bedikah until the burning. But we don’t find such a halacha.

We also see from the Rosh that the reason it is allowed to talk about matters related to the bedikah is not because it actually helps one search, similar to the halacha (Orach Chaim 167:6) that one may say, “Pass the salt” between hamotzi and eating. Rather, the reason is that one must stay focused on the bedikah and make sure to do a good job, and talking about related matters will not distract him. (But, for example, a person would not be allowed to listen to a shiur on some unrelated topic while doing the bedikah, even if he himself does not speak at all.) This explains why Rav Chaim was willing to speak about the halachos of bedikah even though this speaking did not actually help him do his own bedikah.]

Pesachim 23a: Hunters or fishermen who accidentally caught non-kosher animals are allowed to sell them to gentiles. Rashi: This is only if they caught them accidentally, but deliberately doing business with non-kosher food is forbidden, as stated in the Mishnah (Sheviis 7:3). 

פסחים כג ע”א: ציידי חיה ועופות ודגים שנזדמנו להם מינין טמאין ־ מותרין למוכרן לנכריםִ.

רש”י: שנזדמנו ־ דווקא שנזדמנו דלא מצרכינן להו להפקירן, אבל לכתחלה אסור לחזר אחריהן, כדתנן התם במסכת שביעית (פרק שביעי משנה ג): אין עושין סחורה לא בנבילות וטריפות, ולא בשקצים ורמשים.

Rabbi Yehoshua Falk was asked a shailah by the Jewish owner of the kosher slaughterhouse in his town. Sometimes there was no shochet available, but the gentiles of the town wanted meat, and his gentile employees wanted work. Could he tell his employees to slaughter animals and sell them as treif?

Jewish slaughterhouses typically sell to gentiles whatever animals are declared treif, as well as the parts of the animal that Jews don’t eat. This is not considered doing business with treif, because it is an “accidental” by-product of kosher shechitah. But here he would be deliberately slaughtering non-kosher.  

The rav reasoned that although it is forbidden to do business with treif, in this case the Jew would be doing nothing, only telling his gentile employees to do the work. This would depend on the question of whether אמירה לעכו”ם (telling a gentile to do an act forbidden to the Jew) is prohibited only for Shabbos, or applies to all types of aveiros. This question is posed in Bava Metzia 90a (regarding telling a gentile to muzzle a cow while it treads out the grain). He reasoned that we can rely on the Rishonim who say that the question was unresolved, and therefore we are lenient because “telling a gentile” is a Rabbinic prohibition. However, he sent the question to his rebbe, the Chasam Sofer.

The Chasam Sofer replied that if “telling a gentile” had been relevant here, he would have agreed to permit it, both because of the opinion of the Raavad, quoted by the Rosh, that the question is unresolved and we are lenient, and also because many say that the entire prohibition of doing business with non-kosher food is Rabbinic. However, “telling a gentile” doesn’t help us here because in the end, the Jew is the business owner and he is the one making the money off the sale of the meat. The fact that he is not doing the physical work himself is immaterial.

Rather, the Chasam Sofer proposed a different solution: to sell all the animals to the gentiles and have them slaughter, sell and keep all profits for themselves.

Source: Chasam Sofer, Likutim 6:24

Pesachim 9b: If there were nine piles of matza and one pile of chometz, and a mouse came and took from one of the piles, and we don’t know which one – this is the same as the case of “the nine stores”, where we apply the rule of “kavua” and treat it as a 50-50 chance. If a piece got separated from the piles and then the mouse took it – then we follow the majority.

פסחים ט ע”ב: תשע ציבורין של מצה ואחד של חמץ, ואתא עכבר ושקל ולא ידעינן אי מצה שקל אי חמץ שקל ־ היינו תשע חנויות. פירש ואתא עכבר ושקל ־ היינו סיפא. דתנן: תשע חנויות, כולן מוכרין בשר שחוטה ואחת מוכרת בשר נבלה, ולקח מאחת מהן ואינו יודע מאיזה מהן לקח ־ ספיקו אסור. ובנמצא הלך אחר הרוב.

One day in 1949, a woman in Jerusalem went to her freezer to get some margarine to fry schnitzel in. In the freezer there were four identical packages. She took from one at random and used it. Later, she remembered that three of the packages were margarine and one was butter. She rushed to ask Rabbi Tzvi Pesach Frank if the schnitzel was permitted.

Rabbi Frank argued that this seems to be a case of קבוע למפרע, when at the time of the taking, the taker was unaware that one of the “stores” or sources was forbidden, but only realized this in restrospect. The Ran permits such a case, but the Rashba and Ra’ah disagree (Shach 110:14).

Combined with the Ran, we have another reason to permit it: the butter was not forbidden – the problem only began later when she cooked it with chicken – so this is not a case of קבוע. Kavua only applies to an issur. Precedent for this can be found in the Pri Megadim 110 Sifsei Daas 37, who is uncertain as to whether the rule of kavua applies to chometz before Pesach, while it is still permitted. The case of the butter is better than the chometz, for two reasons: 1) Chometz even before Pesach will forbid an endless chain of dishes and foods that touch it (נ”ט בר נ”ט דאיסורא) whereas butter will only affect the first item in the chain, not the second (נ”ט בר נ”ט דהתירא). 2) Chometz is forbidden to nullify even before Pesach as per the rule that אין מבטלין איסור לכתחילה, whereas milk is permitted to nullify in water and later mix into meat (Tzlach in Beitzah).

Furthermore, even the Rashba and Ra’ah, who apply kavua even retroactively, only forbid it as a 50-50 safek. In the case of the schnitzel, the entire issue would only be a Rabbinic prohibition of chicken with milk. Therefore we can apply the rule of תולין, brought in Yoreh Deah 111, that when there are two possibilities of what could have fallen in, with Rabbinic prohibitions we assume the permitted one fell in. However, the pan should be kashered because it is a דבר שיש לו מתירין – there is a way to render it permitted.

Source: Har Tzvi Yoreh Deah 99

Pesachim 50b: If one goes from a place where they work on Erev Pesach morning to a place where they do not work, or vice versa, he must follow the stringencies of both places.

פסחים נ ע”ב: ההולך ממקום שעושין למקום שאין עושין או ממקום שאין עושין למקום שעושין נותנין עליו חומרי מקום שיצא משם וחומרי מקום שהלך לשם.

שו”ע או”ח תצ”ו ס”ג: בני ארץ ישראל שבאו לחוצה לארץ אסורים לעשות מלאכה ביום טוב שני בישוב אפילו דעתו לחזור, וכל זמן שלא הגיע לישוב אפילו אין דעתו לחזור מותר לפי שעדיין לא הוקבע להיות כמותן אבל אם הגיע לישוב ואין דעתו לחזור נעשה כמותן ואסור בין במדבר בין בישוב וכל חוץ לתחום אין נותנין עליו חומרי מקום שהלך לשם.

The Shulchan Aruch (Orach Chaim 496:3) rules that keeping one day Yom Tov in Eretz Yisroel or two days outside of Eretz Yisroel falls in the category of minhag hamakom and is subject to the rule in our Mishnah. However, the Chacham Tzvi (167) disagrees. He writes that minhag hamakom applies only in questions of halacha, where the same halacha applies in all locations, yet different communities follow different opinions. For example, the Gemara says that Eretz Yisroel and Bavel followed two different practices as to whether a certain fat is permitted. What is forbidden fat is forbidden everywhere, but certain places had a minhag to follow the opinion that considers certain fats not forbidden. If the community that considered it forbidden were to move en masse to the other location, they would continue to refrain from eating it, because the prohibition is not dependent on location. But Yom Tov Sheini is not a universal halachic question; it simply depends on whether the messengers of Beis Din reached that particular place. Therefore, people from Chutz Laaretz who are staying temporarily in Eretz Yisroel should only keep one day Yom Tov, just as they would if they had visited during the time when Beis Din sent out messengers.

When the Satmar Rav lived in Eretz Yisroel for a whole year in 1945-46, he kept only one day Yom Tov. After moving to the United States, he made four visits to Eretz Yisroel (in 1952, 1955, 1959 and 1965). He was always careful not to be in Eretz Yisroel over Yom Tov, so as not to run into the dilemma of whether to keep one day and risk doing work on Yom Tov, or to keep two days and risk neglecting the mitzvah of tefillin. Although most poskim agree with the Shulchan Aruch, he felt that as a descendent of the Chacham Tzvi, he should be careful not to violate the Chacham Tzvi’s opinion.

Source: Rabbi Moshe Zoberman, shiur on Taanis 10b

Pesachim 46b: Rabbah said that one who cooks on Yom Tov for the next day does not violate a Torah prohibition because theoretically, guests may come today and eat the food. Although Rabbinically it is prohibited, Chazal made an exception when Yom Tov falls on Friday and one makes an eiruv tavshilin.  

Rema 527:20: One who is fasting on Yom Tov is forbidden to cook for others. R’ Akiva Eiger: This is only when one is abstaining from all food, but if one abstains from a particular food because of a chumra (e.g. kitnios), he is allowed to cook it for others, or even for himself to eat on the following day, since others could eat it today. Maharsham and Chazon Ish disagree with this in the case of kitnios but agree in the case of gebrokts.

פסחים מו ע”ב איתמר, האופה מיום טוב לחול, רב חסדא אמר: לוקה, רבה אמר: אינו לוקה. רב חסדא אמר: לוקה, לא אמרינן הואיל ומיקלעי ליה אורחים חזי ליה. רבה אמר: אינו לוקה, אמרינן הואיל. אמר ליה רבה לרב חסדא: לדידך, דאמרת לא אמרינן הואיל ־ היאך אופין מיום טוב לשבת? אמר ליה: משום עירובי תבשילין. ־ ומשום עירובי תבשילין שרינן איסורא דאורייתא? ־ אמר ליה: מדאורייתא צורכי שבת נעשין ביום טוב, ורבנן הוא דגזרו ביה, גזירה שמא יאמרו אופין מיום טוב אף לחול. וכיון דאצרכוה רבנן עירובי תבשילין ־ אית ליה היכירא.

שו”ע או”ח תקכ”ז ס”כ ברמ”א:  ומי שמתענה ביום טוב אסור לבשל לאחרים אפילו לצורך בו ביום דהוי כמי שלא הניח עירוב שאינו מבשל לאחרים (מהרי״ו).

וכתב המ”ב דהאחרונים חולקים על הרמ”א, וכתב ר’ עקיבא איגר (שו”ת א,ה) דאפילו להרמ”א היינו דוקא במי שמתענה אבל מי שנוהג איסור בדבר מסוים מותר לבשל לאחרים האוכלים אותו, או לעצמו על שבת אם אוכל אותו בשבת (כגון אשכנזי בן א”י המבשל קטניות לאחרון של פסח, הואיל וחולים או ספרדים יכולים לאכלו בו ביום(. והמהרש”ם בדעת תורה (תקכז,א) אסר דלא אמרינן הואיל ואי מיקלעי ליה אורחים כיון שמחזיק אותו כאיסור, וגם החזון איש (מט,טז) אסר מטעם אחר משום מוקצה, אבל שניהם כתבו דמותר לבשל מצה שרויה לאחרון של פסח, דאף המחמירים סוברים דמעיקר הדין מותר שהרי באחרון של פסח אוכלים, ולכך מותר לבשל ביו”ט הואיל ואם בא אורח הנוהג היתר היה יכול לאכלו בו ביום.

R’ Yaakov Kamenetsky told the following story about his great-great-great uncle, R’ Eliyahu Schick.

(R’ Eliyahu Schick’s sister was the grandmother of Chaya Shereshevsky, who married R’ Shmuel Hirsch Kamenetsky, R’ Yaakov’s grandfather.)

Once, while R’ Eliyahu was the rav of Derechin, there was a devasting fire, and he went to collect donations to help families rebuild. He came to the town of Smargon, where his cousin by marriage, R’ Leibele Shapiro (also known as R’ Leibele Kovner), who was the rav of the town, accompanied him. When they came before the home of a wealthy Chabad chassid, R’ Leibele told him there was no use going into that house because the owner would not contribute to anything in Derechin, a shtetl known to be a center of misnagdim. R’ Eliyahu himself was also personally considered to be a fervent misnaged, to the extent that Chassidim accused him of deliberately giving a psak to cause them suffering. In the year 1873, when Pesach fell on Shabbos, R’ Eliyahu prohibited the preparation of knaidlach on Friday for the last day of Pesach because he held that one may cook on Yom Tov for use on Shabbos only such food as one may eat on Yom Tov itself. When R’ Eliyahu passed away a year and a half later, the Chassidim contended that he was punished from Heaven because his ruling had prevented them from enjoying knaidlach on the single day out of Pesach when they were allowed to eat them.

R’ Eliyahu said, “I will bet you a ruble for the Volozhin Yeshiva that I can get a donation from him.” He went in and came out with three rubles. “How did you do it?” asked R’ Leibele. “I told him a story about the Alter Rebbe,” said R’ Eliyahu.

R’ Leibele then said, “You gained three rubles, and here is my ruble for Volozhin, but I cannot accompany you any longer because the Torah commands מדבר שקר תרחק.” 

R’ Leibele was a talmid of R’ Chaim Volozhiner, and his son, R’ Refoel Shapiro, was the Netziv’s son-in-law and successor as rosh yeshiva of Volozhin when it reopened in 1899. R’ Refoel’s son-in-law was R’ Chaim Brisker.

When R’ Leibele was on his deathbed, R’ Yisroel Salanter wanted to visit him, but R’ Leibel refused because he was opposed to the Mussar movement. People said to him, “Is this the time for machlokes?” R’ Leibele replied, “If not now, when? Will I not be going off in a short time to the World of Truth?”

R’ Yisroel Salanter said in his hesped on him, “The posuk in Daniel (8:12) says, ‘Truth will be cast down to the ground.’ What we are doing now is burying truth underground.” The ability to perceive one’s adversary as being truthful – while wrong – because he is consistent in his outlook indicates that R’ Yisroel himself was so unequivocally committed to truth that he had greater esteem for one who was truthful than for one who was in agreement with his Mussar approach.

[R’ Eliyahu evidently held that those who don’t eat gebrokts consider it a real prohibition and therefore cannot take into account the possibility that those who do eat it might show up for a meal – similar to the halacha of kitnios according to the Maharsham.]

Source: Making of a Godol, pages 111-114