גירות

בפשטות קריאת הגמרא היה נראה שבדיעיבד אם גר נתגייר כדי להינשא ליהודית וכדומה הוא גר גמור. אך מהרמב"ם נראה שזה ספק וחוששים לגירותו,
לאחר העיון כך נראה: דהמ"ח בגמרא הוא באופן שידוע שהיה קבלת מצוות אך הסיבה היתה בשביל אישות וכדו' דלחד מ"ד לא הוי גירות אך אנו פוסקים שבדיעבד הוי גירות כיון שהיה קבלת מצוות, אך יש חוץ מזה גם חשש שלא היה קבלת מצוות שלימה ולזה אומר הרמב"ם שמחכים ורואים איך יתנהגו ואזלנן לחומרא, אך אפילו אם יש וודאי קבלת מצוות עדיין לכתחילה ב"ד לא מקבלים ולחד מ"ד אפי' בדיעבד לא חל וע"ע בהגהות הגר"א בשו"ע

brain teaser 13b

I was asked this by a talmich chacham:
תוספות לעיל יג ב' מקשה מדוע צריך פסוק לאשת אחיו שלא היה בעולמו והרי דרכיה דרכי נועם ותי' שם התוספות דצריך פסוק כשהאם מעוברת והו"א שהיבמה תחכה עד שתלד האם . והרע"א מקשה שם שאפילו האם מעוברת יהא מותר ליבמה להנשא לשוק אפילו בלי דין אשת אחיו שלא היה בעולמו דהרי מחצה נקיבות ומיעוטא מפילות ויש רוב שהילוד לא יהא זכר בן קיימא.
ואותו ת"ח ר"ל כך: שמדוע לא תירץ רע"א שצריך הדרשא באופן שיש שני נשים מעוברות שאז יש כבר רוב שאחד מהילדים יהיה זכר בן קיימא. דבשלמא עם הספק היה על האמהות אפשר לפסוק שיש רוב על כל מעוברת אך הספק הוא הרי על האב אם יהיה לו בן קיימא.

Yevamos 20b - 21a - Yibum Works Bidieved

The gemara suggests that yibum is considered "efshar lekayem shnayhem" by doing chalitzah, and then asks "im ba'alu kanu" - meaning that if there were no mitzvah of yibum when chalitzah can be done, yibum should not even work to be koneh bidieved. It seems that the gemara has 2 assumptions: 1. the kinyan of yibum is dependent on the fulfilling of the mitzvah. 2. the concept of efshar lekayem shnayhem does not only create an issur to to yibum but rather makes it that you have not fulfilled the mitzvah of yibum at all. Therefore the gemara asks, that since yibum is koneh bidieved, it must be that chalitzah is not called efshar lekayem shnayhem.

This seems plausible by the concept of efshar lekayem shneyhem, but this will not explain the gemaras question 21a by an aseh not pushing off a lo sa'aseh and aseh. The shita of the rivah is that the aseh does in fact push off the lo sa'aseh (i.e. no malkus), but it is assur to do it since the aseh of yibum does not push off the aseh. It seems clear that acc. to the rivah, if one were to do the mitzvah of yibum, although it is assur to do so, they did in fact fulfill the mitzvah, so why does the gemara say that if one would do yibum to an almanah min hanesuin, it does not exempt the tzarah, which implies that the mishnah was not fulfilled?

sorry for being brief - i am in jerusalem now and don't have that much computer time.

אסור לבטל מצוות יבמין

אסור לבטל מצוות יבמין is this specifically here or is this a general rule in shas that one may not cause a mitzva to be מתבטל?
I found the ברכ"א discusses this, he comes out that's its zika oriented as may -for example- be מפקיר his fruits to become פטור from תרו"מ

What is זיקה

the ברכת אברהם brings an argument if the concept of זיקה is מדרבנן or מדאורייתא. The proof that it is דאורייתא is from the fact that the יבם can be מפר the נדרים of his יבמה if one holds of זיקה.

He offers an explanation of sorts to this idea. The idea of being מקודשת makes a woman forbidden to the whole world and designated for one man. Yibum id similar in that she is forbidden to the world and designated for the brother. In the case of 2 brothers only one of the qualities of קידושין are there as she is forbidden to the world but not designated to a specific brother. This is why some hold that only by one brother there is זיקה. At the end, even if one holds of זיקה it is not a regular דין קידושין as one may marry the sister of his חלוצה and many other such examples.

Yevamos 16a - Exiting Through 3 Different Doors

The gemara tells that R' Elazar Ben azarya, R' Yehoshua and R' Akiva all exited through different doors. Tosafos explains that they did this in order to avoid Yonasan Ben Hurkinas who would prove the opinion of Beis Shamai to be correct and they would have to establish the halacha like B"S to do yibum to a tzaras ervah. The obvious question is, if they knew that Yonasan would prove his position that Beis Shamai was correct, how are they allowed to deliberately avoid him? R' Elchonon (divrei sofrim 5:15) explains that these 3 Rabbonim had a kabbalah from Chagai Hanvi that B"H position is correct. But, they realized that Yonasan would be smarter than them and present arguments and proofs that they would not be able to refute. Ain l'dayan ela mah sh'einav ro'os, so they would be forced to submit and pasken like B"S, even they knew that B"H was correct. Therefore, they avoided Yonasan so as not to hear his proofs so that they can continue holding like B"H. He continues to explain that in the machlokes B"S and B"H in general, we now pasken like B"H only bec. we can't grasp the true opinion of B"S who were much sharper, but in the world to come, when we will be enlightened to higher levels of understanding we will follow Beis Shamai.

This reminds me of a story from the sridei eish that he writes about the rogotchov - see comment #1.

I will be away for a little while starting sunday - R' Yossi and R' Aryeh please start posting!!

Yevamos 15a - Agudos and B"S following their opinion

There are many difficulties with this sugya.

1. The gemara 14a asks on the opinion that b"s practiced their opinion regarding the tzaras ervah, how can they do that, what about lo tisgodidu. What is the gemara suggesting that they do instead, can they allow a yevama leshuk just to avoid lo tisgodidu (perhaps chalitzah would have been a solution, but that should also be lo tisgodidu since b"h didn't require it)?

2. Also, why does the gemara ask only on b"s that if they practiced their opinion it would be an issur of making agudos, why not ask the same question on b"h - who says it was b"s that was causing the split, maybe it was b"h?

3. Tosafos 15a d.h. v'sicheich, proves from the gemara that acc. to the opinion that b"s followed the practice of b"h, that is even when b"h was lenient. How can b"s submit and follow b"h to be lenient since they held that it is assur?

4. The rashash points out that rashi 15b states explicitly as the gemara strongly implies, that the opinon who says that b"s did not practice their opinion, that is only to avoid making agudos agudos, but the gemara 14a says clearly that the rationale for not practicing their opinion is that they were sharper and/or don't care about the bas kol?

5. Since the gemara concludes that there is no issur of agudos between b"s and b"h bec. they are different batei dinim (either in 2 cities acc. to abaya and even in 1 city acc. to rava), how can rashi explain that the opinion who says that b"s did not practice what they held was bec. of agudos?

See comment for a mehalech.

Yevamos 14a - Lo Tisgodidu

Tosafos asks why there is no issue of Lo Tisgodidu by the fact that the cities and villages read on different days. Tosafos answers that it is impossible to suggest that the reading was done by the city person for the villagers, bec. on the day prior to the 14th the city person is not obligated in the mitzvah of reading and cannot read for others. Therefore, the villagers must of had a village person read for them. Thus, they had no need to come to the city to read, rather they read in their village, in which case it is like 2 batei dinim in 2 different cities so there is no problem of Lo Tisgodidu. Rashi in Maseches Megillah 2a writes clearly that the city person read for the villagers (rashi considers the city person to be a bar chiyuva even on the earlier day - see ritvah there). Rashi clearly holds that the villagers came to the city to hear the megillah, so the question of Tosafos is still applicable, since there are 2 customs being maintained within 1 city, it should be a problem of Lo Tisgodidu? It seems to me that Rashi himself 13b understands that the issue of Lo Tisgodidu was only considered a problem between the walled and non-walled cities since the walled city people cannot read on the 14th, and the non-walled city people cannot read on the 15th - that is 2 entirely separate customs. But, the villagers who ideally should read on the 14th as well and can actually read on the 14th, just that chazal were lenient on them and allowed them to read earlier, there is no issur of Lo Tisgodidu at all for them to read in the city prior to the 14th.

Yevamos 13a - Tzaras Tzara: Rav Ashi

The gemara is looking for a source for tzaras tzara (acc. to rashi - see tosafos 2a that we are looking for a source for tzaras tzaras tzara....). Rav Ashi says that just as the tzara is bemakom the ervah, so too the tzaras tzara is bemakom the ervah. Rashi on the mishna 2b (and also 8b d.h. im kein) seems to understand that since the ervah exempts her tzara, the tzara is herself an eishes ach not b'makom mitzvah, therefore she herself is an ervah of eishes ach which will assur the tzaras tzara. However, R' Elchonon (siman 3:15) explains that the pesukim teach us that b'makom mitzvah the tzarah herself becomes assur with the same issur as the ervah. If the ervah is a daughter, then the tzara of a daughter will be like a daugher in regard to the exemption from yibum. It is not the issur of eishas ach that exempts the tzaras tzara, but rather the original ervah of bito.
The approach of r' elchanan assumes that there would not be an issur eishes ach placed on the tzaras ervah since she fell b'yibum, and there would only be an issur of "bito". This would answer why we need a source for tzaras tzara (either a pasuk or sevara) and we don't simply say that a tzaras tzara is really just a tzaras ervah of eishes ach. We would have thought that the issur of bito becomes diluted and can't pass on to tzaras tzarah, and therefore we need either a pasuk or sevara to be mechadesh that it does.

Yevamos 13b - Is the Mitzvah Dependent on the Issur?

I assumed that the mitzvah of yibbum depended on the situation of eishas ach, but not on the issur of eishes ach. It just so happens that in the situation of eishas ach there is also an issur. However, Rashi explains that acc. to beis shamai who is matir the tzaras ervah in yibum bec. the issur of "aishes ach" isn't chal on the preexisting issur of a daughter. Since the issur of "aishes ach" is not chal on the ervah, the ervah doesn't fall b'yibum and it is as if she is not here at all so she does not exempt her tzarah from yibum. Clearly Rashi explains that the mitzvah of yibum isn't just dependent on the situation of being married to a brothers wife, but is dependent on there actually being an issur of aishes ach. This sheds new light on the concept of mitzvaso bekach as it applies to yibum. The torah specifically gave this mitzvah only in a situation of issur. Similarly we can explain by kelayim in bigdei kehuna - it is not just coincidental that the torah wanted the kohens clothing to be made from wool and linen which happen to be an issur of kelayim. Rather the mitzvah of bigdei kehuna is to wear clothes that are a violation of the issur kelyaim.

Yevamos 12b - 3 Women Who Can Have Relations with a Moch

R' Elchanon (kovetz hearos siman 23) discusses whether it is permitted for a person to put themselves into a situation where they will have to use pikuach nefesh to permit an issur. He proves from the Ba'al Hameor who forbids leaving on a ship within 3 days of Shabbos because it is likely that you will find yourself in a situation of pikuach nefesh and have to be mechalel shabbos, that it is only an issur derabonon but not deoraysa (if it would be an issur deoraysa it should not matter if it is within 3 days or more than 3 days). Once it is only an issur derabonon, we can be matir for shalom bayis. Therefore, one would be allowed to have relations with a women for whom it is dangerous to become pregnant, even though after relations she will use a 'moch' to prevent pregnancy (i am not sure about the statistical success rate associated with this form of birth control). This explanation would be necessary if we learn the gemara to be speaking about a moch after relations (tosafos in the name of rabbeinu tam) and would be an issur if not for pikuach nefesh. But, according to Tosafos who explains that these 3 women MUST use a moch, which implies that other also are allowed to bec. there is no issur for her to remove the shichvas zerah with a moch after tashmish, we don't need to come onto the heter of pikuach nefesh. Rav Elchonon second guesses his proof, that perhaps there is an issur deoraysa to put oneself into a situation where pikuach nefesh will have to push off the issur and no proof can be brought from the ba'al hameor bec. he may hold that shabbos specifically is "hutrah" for pikuach nefesh (but other issurim which are only "dechuya" there would be an issur deoraysa to lichatchila put oneself into a situation where they will have to rely on the license of pikuach nefesh).

At the end he cites a magen avrohom (o.c. 248) who questions whether one who intentionally put themselves into a situation of pikuach nefesh should rely on it to be docheh shabbos. R' Elchonon explains that by not relying on the heter it comes out retroactively that he did not do an issur by placing himself in that situation. R' moshe has a teshuva where he adamantly disagrees and says that one must use the heter of pikuach nefesh to be docheh shabbos and save their life.

Yevamos 8b - What is Matir the 2nd Biah

Tosafos points out that although we need a pasuk to be matir remarriage after divorcing a yevama, we don't need a pasuk to be matir the 2nd biah, yet when it comes to a chayvei lavin i.e. a divorced women who falls b'yibum to a kohen, the first biah is permitted but the 2nd is not. Why? Tosafos answer is not so clear, but the Tosafos Yeshanim seems to say that if we are "matir" the issur by the first biah, it remains mutar bec. it is not logical that the torah would create an issur by the 2nd biah. But, by chayvei lavin where we are relying on aseh docheh lo s'aseh for the first biah, since the 1st biah is not permitted, rather it is "pushed off", the 2nd biah will be assur.

Tosafos doesn't seem to be saying this exactly. I pointed out from Tosafos earlier that mitzvaso bekach is not necessarily synonomous with "hutra". Therefore, Tosafos could hold that even by the standard case of yibum, although it is mitzvaso bekach, it is only dechuya, not hutra. So the question comes back, Why does the mitzvah of yibum push off the issur of eishes ach even by the 2nd biah, but by a divorcee to a kohen it will only push it off by the 1st biah? What does Tosafos mean by his answer?

Yevamos 7b - Tamei entering Mikdash

The gemara says that a metzorah who is a tevul yom from keri should not be able to stand in machaneh leviya, and he should also not be able to stick his thumbs into machaneh shechina (since partial entering is called entering). The heter for the tevul yom to stand in machaneh leviya (sha'ar nikanor) is that the aseh of korban pesach pushes off the issur of tevul yom in machaneh leviya. But the heter to stick his thumbs into the azarah (machaneh shechina) for behonos is "ho'il v'ishtri" - meaning since we allow him to stick his hands in when he is a metzorah who is automatically mechusar kippurim (and not allowed in machaneh shechina), we also permit him to stick his hands in from the perspective of tevul yom.

Tosafos asks that once we allow him to stick his hands in and we hold that partial entering is a violation of entering, we might as well allow him to walk into the machaneh shechina. Tosafos answers: 1. The issur to go in partially is learned from a hekesh, so we are matir that issur. But the issur to walk in is mefurash in the pasuk, and we are not matir that issur. 2. He is required to reduce his "entry" as much as possible, so since he can accomplish what he needs by sticking his thumbs in, he is not allowed to walk in.

It seems that acc. to the first answer of Tosafos he can stick his entire arm in, since that will still only be a partial entering, but acc. to the 2nd answer he can only stick in the minimum that is necessary i.e. his thumbs but not even his hand and certainly not his arm.

Yevamos 6a - Listening to Parent to do an Aveira

The gemara seems to assume that when a father tells a son to do an aveira there is a mitzvah of kibud av, the only discussion is whether this mitzvah of kibud av is strong enough to push off a lo sa'aseh sheyesh bo kareis. Even Tosafos 6a d.h. nigmar, who says that once we are told that kibud av is not a special strong aseh, we assume it is a weaker aseh and does not even push off a regular lav, still assumes that there is a mitzvah to listen to a father when he tells you to do an aveira, just that it doesn't have the strength to push off an issur.
The Maharatz Chiyus asks based on the gemara in B.M. 62 that if a father is not "oseh ma'aseh amcha" i.e. a rasha, there is no mitzva of kibud av at all. Acc. to this opinion, anytime a father tells the son to do an aveirah he is automatically not oseh ma'aseh amcha, and there is no mitzvah of kibud av at all! How can the gemara assume that there is a mitzvah just that it doesn't override an issur?

Maharatz Chiyus quotes from the Shita Mikubetzes that if the aseh would push of a lo sa'aseh, the father would not be doing anything wrong by telling the son to violate shabbos or do an issur. It is only once we say that kibud av is not docheh the issur that it is considered something wrong. He concludes with a very strong question. Based on the conclusion that the fathers command to do an issur does not push off the issur, thereby making the father an oseh ma'aseh amcha, the reason the son should not listen is simply bec. there is no mitzvah of kibud av at all. So, how can the gemara think to learn from the lav of mechamer to all other places that aseh is not docheh lo sa'aseh, perhaps it is only by chibud av where there is no mitzvah at all to listen, but by other places we would learn from kelayim b'tzizis that aseh is docheh a lo sa'aseh.

יבמות ה' עשה דוחה תרי לאוין

הראה לי אחד המנ"ח ברנ"א שמקשה על רש"י, שרש"י לומד דאחר שנלמד מ'ראשו' של מצורע כבר צריך 'עליה' דאחות אשתו דהו"א העשה ידחה הלאו, ודברי רש"י תמוהין דעדיין לא ידעינן שעשה דוחה לאו שיש בו כרת. ומכח זה לומד המנ"ח דתרי לאוין חמירין כעין כרת, והכא יש תרי לאוין של מקיף ןניקף (!) ולכן למסקנה שעשה לא דוחה לאו שיש בו כרת ה"ה לא דוחה תרי לאוין, חוץ מאצל נזיר דקיל ושם מפורש בתוס' נזיר שכן דוחה אפי' תרי לאוין

יבמות ו ע"א

שיטת רש"י מפורשת שלמסקנה את שבתותי תשמורו שבמצות כיבוד אב ושם בא לאפוקי שחוט לי בשל לי, דהיינו שלמסקנה יש מקור שעשה דוחה ל"ת שיש בו כרת היכא שהוי הכשר מצווה ואין דרך אחרת לקיים העשה. לפ"ז מאד תמוה לי מה ההו"א בגמרא שאת שבתותי תשמורו שבמצות מורא מקדש בא ללמד באם אינו ענין שעשה דוחה לאו וכו' והרי איצטריך לגופיה למימרא שאף שלמדנו מכיבוד אב שעשה דוחה לאו בהכשר מצוה כאן לא דוחה, דהיינו דרק אפשר ללמוד שעשה דוחה וכו' אי לא איצטריך לגופיה (כמבואר תוס' ו ע"ב) והכא הרי איצטריך לגופיה
ואחד תירץ לי שכיון שהיסוד שנלמד מכיבוד אב הוא שאתם חייבים בכבודי ה"ה שכולל את מקדשי תיראו שכל דין המקדש הוא ליזהר בכבודי ולכן היינו יודעים אפילו בלי פסוק שלא ידחה, מה דעתכם

Yevamos 5a - Mitzvaso bekach

Tosafos on 3b explained that we can't learn aseh docheh lo sa'aseh from the standard case of yibum where we push off eishes ach, bec. that is "mitzvaso bekach". Simply speaking this means that since the mitzvah of yibum only exists in contrast to the issur, the issur could never have been given when up against the mitzvah of yibum. Meaning, mitzvaso bekach would indicate that it must be hutra rather than dechuya.

However, Tosafos 5b is clear that although kelaim in bigdei kehuna is "mitzvaso bekach" and therefore cannot be used as a source to learn from (as Tosafos says by the standard case of yibum), it is not b'geder hutra, rather it is dechuya. Tosafos says that bigdei kehuna is not a weakness in the prohibition of kelaim, bec. we are not matir the issur of kelaim (which would indicate its weakness), rather we push it off b'geder "dechiya" as we would in any aseh docheh lo sa'aseh. Clearly Tosafos holds that "mitzvaso bekach" does not force us to understand that it is hutra rather than dechuya. Even though kelaim bb'igdei kehuna is mitzvaso bekach, it follows the regular format of dechiya i.e. aseh of avodah is docheh the lo sa'aseh.

עשה דוחה ל"ת - מחשבה

to take a break from the head spinning sugya...
We touched on this once before, why is it that an עשה overrides a לאו and yet the punishment for transgressing a לאו is much stricter that one for not fulfilling an עשה?
I once heard from a Rebbi of mine like this: If one is used to bringing flowers to his wife every week and forgets once, he might be in trouble but has hope, if however he is caught cheating once he is in real trouble. Still if one would be married and not cheat ever but also not do anything positive to the marriage, he is in fact 'not married'.
another example, if a trucker is hired to truck a load cross country and the owner warns him not to go beyond speed limit and not to crash the car etc. if the trucker does everything perfectly but doesn't unload the goods at his destination but goes and comes back with the same load, what good does it do for us that he obeyed the speed limit.
meaning, that our job is to accomplish in this world and 'build the love', therefor this building overrides the transgressions, because the לאוין are only there to protect what has been build not to suffocate the building. There is a Gaon in Mishlei (6:36) that says 3 מלאכים greed a person after 120' 1 to count his עשה,s 1 the לאוין and one to see what he accomplished as far as his תפקיד and he says that last one is familiar, because he was the one to teach you תורה in the womb, meaning to teach you your true essence.

3a

when is the daughter of one's wife become אסור to him, is it after קידושין, נישואין or only after ביאה? Tosfos clearly says you do not need ביאה although the pasuk says ערוות אשה ובתה however the פתחי תשובה understands in tosfos that you need נישואין the Rambam holds that קידושין is enough to make her asur. (forgive me for not giving the מראה מקומות it's in the ברכת אברהם),
just a point, I think Tosfos might just mean that the pasuk is not literal and you need not wait till ביאה but perhaps he agrees with the rambam? in any case the achronim say not like me. let me know if you want the sources.

Yevamos 3b - Question of R' Akiva Eiger - Tzaras Ervah

One of the questions that is dealt with most extensively in the achronim and really opens up the perspective of the sugya of tzaras ervah is the question of R' Akiva Eiger. He asks why do we need a pasuk of "litzror" mentioned in the braisa, to tell you that tzaras tzarasa is also exempt from yibum. The mechanics of why a tzara is exempt is that since there is an ervah (Sarah), and this co-wife is a tzaras ervah (Esther), there is no zikah to yibum when her husband (reuven) dies, therefore she (Esther) becomes a regular issur eishach ach to the yavem (shimon). So, when the other brother (Levi) does yibum to the tzaras ervah (Esther), and then Levi dies, neither this women (Esther), nor Levi's other wife (Michal) have zikah of yibum to Shimon. The reason is that since the tzarah (Esther) becomes a regular issur of eishes ach to Shimon, that was created by Reuven, so the issur eishes ach on her preceded the relationship that is making her fall now to yibum from Levi, she (Esther) becomes in her marriage to Levi, like a regular issur ervah herself to Shimon, who exempts her tzarah (Michal). Based on this logic we should not need a pasuk to tell you that a tzaras ervah exempts tzaras tzarasa, bec. every tzaras ervah becomes an ervah herself and exempts her tzara as a tzaras ervah!

Yevamos 2a genius

The ברכת אברהם brings the following question from one of the עילויים of Europe - העילוי ממייציט:

If אשת אחיו מאמו is not in the Mitzva of יבום and is an איסור כרת then how come when there are 2 FULL brothers that share a father and mother isn't there a problem of doing יבום to an אשת אחיו מאמו, although she is also an אשת אחיו מאביו it should be forbidden because she is also an אשת אחיו מאמו.

The ברכ"א answers: the name of the איסור is אשת אחיו whether its a brother from a shared father or a shared mother, the "name" is still a "brothers wife", in a case when there is a חיוב of יבום it unlocks the איסור, so in a full brother since there is a חיוב the מצוה applies. simple. genius.

Chagiga 27b - Was the Shulchan Transportable?

Tosafos explains that we consider the shulchan not to be "asui l'nachas" bec. they picked it up to show for the olei regel, but the fact that it was transported through the midbar does not make it loose the status of "asui l'nachas" bec. "it was moved along with the other keilim". It is not so clear to me what Tosafos means. Why is the fact that other keilim are also moved make it not "asui l'nachas"? I don't have a clear peshat but it reminds me of the gemara shabbos 31b that since "al pi hashem yachanu" the taking down of the mishkan is considered destroying in order to build in its place. Meaning that the Mishkan was considered to always be in the same place. Since the Shulchan was moved along with the keilim of the mishkan, it still maintains the status of "asui l'nacha", if not for the fact that it was shown to the olei regel.

MAZAL TOV ON SEDER MOED!!!

WE SHOULD ALL BE ZOCHEH TO LEARN MANY MORE SEDARIM U'LSAIMUM.

Chagiga 25 - Eretz Ha'amim, Lifnei Iver, Migu

2 questions and 1 hearah:

1. Tosafos asks that if there is a retzuah seperating galil from jerusalem, how can one be oleh regel and still be tahor? Hagahos Ransburg says that he can get there by putting a board on an ox. Why can't we use that trick to get wine to jerusalem? He answers that it is similar to Eiruv in a cemetery where the maharsha explains that using this trick is not considered access to the eiruv since it is not a common way to travel. I don't understand the connection! By eiruv we don't consider this method as having "access" since it is not a common means of travel, but if someone shows up with wine in jerusalem that they brought from gallil on the back of an ox, why is that not acceptable for nisachim?

2. Rashi explains that if the 2 brothers split wheat and the chaver takes the tahor and give his brother the tameh, that is fine. But he cannot "sell" the tameh barley to his brother, to ensure that he receives the tahor wheat, since he is providing him with an issur and is violating lifnei iver. Why in the first case is it not lifnei iver? Had the chaver taken the tameh and thrown it out his brother would take the tahor and avoid any issur, so by the chaver taking the tahor he is causing (trei avri d'nahara) his brother to do an issur!? We see from here a big yesod. The issur of lifnei iver is to pass wine to a nazir since you are passing to him issur. But if there is one cup of wine and one of water in front of the nazir, one may take the water even though they will be causing the nazir to drink the wine. It is only lifnei iver to pass him the issur, but one may take the heter and thereby cause him to do his own issur.

3. The migu in our gemara is since we believe him for the kodesh in this barrel we automatically believe him for the terumah in it since they are 1 unit together in a barrel. Similarly, since we believe his body is tahor for pesach we beleive him for terumah since his body is 1 unit. Why does rashi have to explain the migu that to beleive him on the kodesh and not teruma is "degrading for the mizbeiach", just say that it is one unit that can't be split?