This is a rather large dispute among the Rishonim, the early commentaries.
See the Rashba (שו״ת ח"א תרפט):
ולי נראה שהכל תלוי במחלוקת אם נאמר שבת דחויה או נאמר שבת הותרה אצל
חולה. אם נאמר שבת הותרה אצל חולה שוחטין לו שלא אסרה תורה מלאכת שבת אצל
חולה. ושוחטין לחולה בשבת כדרך ששוחטין אנו לעצמנו... אבל למ"ד דחויה היא
מאכילין לו הנבילה שהוא צריך לאכול ...
As far as I know, the above answer is correct. A neveilah conveys ritual impurity, while a treifa does not; as per the gemura in Niddah on 42b (about 3/4 of the way down the daf), which makes a drasha from the pasuk in Vayikra 22:8.
You're not mistaken: in fact the Tur and Shulkhan Arukh (335:2) say that only a בן גילו has the ability to take some of the sickness with him. This difficulty was recognised by the Drisha on Ramba"m and he stresses Ramba"m's wording: כאילו נטל חלק מחולייו - it is as if he takes part of the illness. However, there's a note in my Ramba"m that directed me to ...
If all conditions are right for the Asei to override the Lo Sasei, then it is permitted. Otherwise, it is a Mitzva haBa bAveira.
Among the conditions that must be met:
Fulfillment of the mitzva must occur at the same time (or with the same action) as the Aveira (Beitza 8b: בעידנא דקא מעקר לאו קא מוקים לעשה)
It isn't possible to avoid the conflict by ...
The gemara (Nedarim 2b) says explicitly what the difference is between a neder and a shevuah:
דתנא נדרים דמיתסר חפצא עליה... לאפוקי שבועה דקאסר נפשיה מן חפצא
It taught nedarim where one forbids an object on himself, and excluded shevuot where one forbids one's self from the object.
This distinction follows through to the Rambam (first two halachot in ...
UPDATE: msh210 beat me to it by a few seconds, but I'll post anyhow so you see the similarity between our answers.
Try this page on the Brisk method.
A hakira seeks to suggest two subtly-different explanations for something. If explanation A is correct, then X should apply in some other case; if explanation B is correct, then Y should apply instead.
Literally it means "investigation" or something similar (and is used in other contexts, like that of evidence in court), but it's used to mean "hair-splitting".
Well, almost really. A chakira is an investigation as to the exact nature of something, and is usually stated as a binary choice: is X an A or is X a B? (X can be an object, a state, ...
Look at the Haga'ot HaGRI"V 26 on the "Klalim B'Rashi", printed after the Mavo LaTalmud, at the end of Masechet Berachot.
דרך רש״י בהרבה מקומות לפרש המשנה כס״ד דמקשן כדי להבין המשנה כס״ד טרם בואו אל המסקנא וזהו אך דרך
רש״י לא כן שאר מפרשים תוי״ט פ״ב דפאה מ״ב
It is Rashi's way in many places to explain the Mishna according to the ...
There are two different types of gzeirah shava
specific words were part of the mesorah but the pesukim used and / or the actual item that was derived from the gzeirah shava may not have been part of the mesorah.
The content of the limud was part of the mesorah but not the words used in the gzeirah shava.
Halichos Olam Shaar 4. See also Ramban sefer ...
Shehechiyuanu is a brikat hashevach.
Now I have to explain to you how every instance of shehechiyanu is really recited after the occasion.
On seeing a friend after 30 days or hearing good news that benefits only myself (I include here one who heard of rain after a drought): I think we all agree these are after.
On acquiring new property: The shulchan aruch ...
See the Aruch HaShulchan YD 87:10 where he says that you cannot bring a proof from the laws of Shabbos to say that frying is a problem of cooking meat and milk. Similarly, by smoking (in #25) he writes the same. In #31 he discusses bishul acher bishul, but seems to conclude that again, despite the rules of Shabbos, the rules of basar b'chalav are different.
Bavli Chullin 10b:
מנא הא מלתא דאמור רבנן אוקי מילתא אחזקיה? אמר רבי שמואל בר נחמני אמר ר' יונתן, אמר קרא: ויצא הכהן מן הבית אל פתח הבית והסגיר את הבית שבעת ימים, דלמא אדנפיק ואתא בצר ליה שיעורא! אלא לאו משום דאמרינן אוקי אחזקיה.
Whence do we know that which the Rabbis said, "establish it based on its previous status [Chazaka]"? Rabbi Shemuel bar ...
Rambam (Hil. Nedarim 3:7) draws exactly this distinction, based on Nedarim 16b. He says:
ומפני מה נדרים חלים על דברי מצוה. ושבועות אין חלות על דברי מצוה. שהנשבע אוסר עצמו על דבר שנשבע עליו. והנודר אוסר הדבר הנדור על עצמו
Translation from Chabad.org:
Why do vows take effect with regard to mitzvot and oaths do not take effect with regard to mitzvot? ...
Rabbi Aqiva Eiger (shu”t #136) says that there are two types of doubt, and each has its own mechanism for birur, for clarification.
The case of qavu’ah is one where the reality was once established. So in principle, there is a specific halakhah assigned already to this case. The doubt is in what that halakhah is. In this situation, we do not invoke rules ...
The principle of עשה דוחה לא תעשה tells one how to act when there two conflicting imperatives or obligations from the Torah. For example on one hand the Torah is commanding you to attach wool tzitzit to the four cornered garment. On the other hand the Torah is commanding you not to mix wool and linen. These are two conflicting imperatives that you must ...
To answer a mistaken premise of the question -- boneh is possible on the human body.
See Shabbos 107a:
המפיס מורסא בשבת אם לעשות לה פה חייב אם להוציא ממנה לחה פטור
If someone pops a pimple on Shabbos -- if he did so to make an
opening, then he is liable for punishment; if he intended to remove
the pus from inside, he is not liable
Rashi there ...
Rashi's shittah is to explicate the gemara - not to provide a stand-alone peirush on the Mishna. As such, you will find that his interpretation of any given mishna will vary depending on the context in which the gemara is quoting it. To give you an example, consider Shevi'it 4:10. There, the mishna asks and answers a question as follows:
מאימתי אין קוצצין ...
I once asked a rebbi of mine this very question, in a different context. The Gemara in Kiddushin 14b discusses a Gezerah Shavah using the word שכיר, a word that is found a number of times in the sections of the Torah that deal with slaves/servants. Tosofos there, s. v. מוכר, takes the liberty of applying this Gezerah Shavah to other instances of the word in ...
As the other answers stated, the main difference between נבילה וטריפה is the טומאה. However, there are also other differences, such as אותו ואת בנו (see שמלה חדשה טו); in שלחן ערוך פב where ביצת טריפה is אסור but ביצת נבילה is not; and (lamely) someone who makes a vow נדר not to benefit from one but left the other alone. These are found all over שמלה חדשה ...
On your way, you may suddenly realize that you have something in your pocket. At that point, it would certainly be assur to continue to carry it. Checking your pockets prevents you from being in this situation so it is not a gezeira legezeira.
If I'm reading the Mishna right, the case of ודאי על הדמאי means you take some real Tevel Maaser Rishon and declare it all Terumat Maaser for the Maaser Rishon you separate from the Demai. If the Demai needs it, then such a declaration works and the real Tevel Maaser Rishon is now real Terumat Maaser. If the Demai doesn't need it, then the real Tevel Maaser ...
Besides for the Tosafos Yom Tov cited by @Menachem there are a couple of other sources:
R. Yechezkel Landau, in his commentary to Berachos 20a, writes:
ונראה לפי הכלל שאני רגיל לומר לתלמדיי שדרכו של רש"י תמיד בהמשניות לפרש
המשנה לפי ההוה אמינא של המקשה ולא לפי המסקנא כדי שיהיה שייך סוגית
הגמרא על המשנה כסדר
And this is apparently in accordance ...
See the Minchas Chinuch mitzvah 32 after he lists all 39 melachos, right after Hotzaah, page 177 in the new editions, he goes into pikuach nephesh he says the Rambam and most poskim (according to the Kessef Mishna) hold it is dechuyah while Rabbeinu Meir brought in the Rosh say it Hutrah.
I don't have Kahati but from the Bartenura I will say that we are dealing with a legality in the second case that doesn't apply to the first. In the second case the plaintiff points to the big ox and says this one damaged mine. To which the defendant responds by pointing to a different, smaller ox and says no, this one did. Now, although value wise the ...
Therefore the Lord will take no pleasure in the young men, nor will he pity the fatherless and widows, for everyone is ungodly and wicked, every mouth speaks vileness. And for all this, his anger is not turned away, his hand is still upraised.
As @GershonGold pointed out, the Talmud (Shabbos 33a) derives from here that nivul peh is a very ...
The main Gemara is Nedarim 39b:
אמר רבי אחא בר חנינא כל המבקר חולה נוטל אחד מששים בצערו אמרי ליה אם כן ליעלון שיתין ולוקמוה אמר ליה כעישורייתא דבי רבי ובבן גילו
Said Rabbi Acha Bar Chanina: anyone who visits the sick takes away 1/60th of their pain. [The rabbis] responded to him: "if so, couldn't we just bring sixty people in, and boom he'd get ...