Tuesday, 26 November 2013

Understanding Rashi's Take

Our recent post about אין אדם משים עצמו רשע left a question open: how does Rashi's understanding jive with the principal of עדות שבטלה מקצתה בטלה קולה? Our principal allows us to only invalidate part of the testimony, while that principal says that once part of the testimony is invalidated, all of it is invalidated.

Take 1: Legal Loophole

This article, by Rav Ofer Fried, presents it as a legal loophole that the judges can use to get around the problem of the testimony being invalidated by a blood relation. The assumption is that the division of the witness' testimony into different pieces is subjective and the judges can do this at their own discretion:

מ"מ, לכל הראשונים הללו, ה'פלגינן' הוא פעולה שעושה בית הדין כדי לפטור את הבעיה של 'עדות שבטלה מקצתה בטלה כולה'.

This answer is a bit unsatisfying, though. In general we would prefer to understand the concept as some general fundamental rule, rather than a subjective technicality to be applied at the Judge's whim.

In Pursuit of a More Fundamental Answer

I asked Rav M about this and he gave me a couple of more fundamental answers in brief. After learning up the source for עדות שבטלה מקצתה בטלה קולה, this is how I understand his answers.  Let's start out by looking at the relevant gemara(בבא קמא עג א)

תנן גנב על פי שנים וטבח ומכר על פיהם ונמצאו זוממין משלמין את הכל מאי לאו שהעידו על הגניבה וחזרו והעידו על הטביחה והוזמו על הגניבה וחזרו והוזמו על הטביחה ואי סלקא דעתך למפרע הוא נפסל הני כיון דאיתזמו להו אגניבה איגלאי מילתא למפרע דכי אסהדו אטביחה פסולין הוו אמאי משלמין אטביחה אמרי הכא במאי עסקינן כגון שהוזמו על הטביחה תחילה אמרי סוף סוף כי הדרי מיתזמי אגניבה איגלאי מילתא דכי אסהדו אטביחה פסולין הוו אמאי משלמי אטביחה והלכתא שהעידו בבת אחת והוזמו 

לימא כתנאי היו שנים מעידין אותו שגנב והן מעידין אותו שטבח והוזמו על הגניבה עדות שבטלה מקצתה בטלה כולה הוזמו על הטביחה הוא משלם תשלומי כפל והן משלמין תשלומי שלשה א"ר יוסי בד"א בשתי עדיות אבל בעדות אחת עדות שבטלה מקצתה בטלה כולה מאי בשתי עדיות ומאי בעדות אחת אילימא בשתי עדיות בשתי עדיות ממש בשתי כתות בעדות אחת בכת אחת בזה אחר זה וא"ר יוסי בעדות אחת בכת אחת בזה אחר זה כי מסהדי אגניבה והדר מסהדי אטביחה כי מתזמי אטביחה עדות שבטלה מקצתה בטלה כולה ואיתזמו להו אגניבה מהיכא תיתי הך אלא לאו בשתי עדיות בעדות אחת כעין שתי עדיות ומאי נינהו כת אחת בזה אחר זה אבל בעדות אחת בבת אחת לא וסברוה דכולי עלמא תוך כדי דיבור כדיבור דמי...

The gemara brings a number of sources about עדות שבטלה מקצתה בטלה קולה and contemplates the interpretation of the various opinions. In any case, it seems that the principle would apply according to all the opinions in a case like ours in סנהדרין ט ב where the two testimonies come as part of the same sentence. So how do we reconcile this source with our own?

Take 2: Limiting the Principle to Plotting Witnesses

While our sugya discusses a witness disqualified as a blood relative(according to Rashi), the sugya in Bava Kama is dealing with a case where the witnesses were found to be עדים זוממים. Perhaps עדות שבטלה מקצתה בטלה קולה only applies to the latter group, where the witnesses have been shown to be dishonest people, but in the case of disqualification of a blood relative we say מפלגינן בדיבורא and allow the second testimony to stand.


Take 3: Two Testimonies for Two Defendants

In the case in Bava Kava, the two testimonies both relate to the same theft by the same thief, the question being as to the severity of the theft. In Sanhedrin, on the other hand, the two testimonies are about two different people, engaged in the same act: the accused and the witness himself. Maybe in the latter case, where two different people are concerned, Rava views the testimony as two separate testimonies, while in the former he views it as one.

A Wider Range

 So while we concluded last time that both understandings of אין אדם משים עצמו רשע are pretty similar, we have a wider range of views of the principle of עדות שבטלה מקצתה בטלה קולה. On one hand we have the Raavad's view of Rav, that it's a כלל גדול, a general principal in the disqualification of testimony. On the other side of the spectrum, it may be limited to עדים זוממים or only applicable when the two testimonies are about different aspects of the same act by the same defendant.

Monday, 25 November 2013

אין אדם משים עצמו רשע

This one is actually from a class that I missed, but got the source sheet for. I also heard a brief oral synopsis of the class.

Debate Over Partially Disqualifying Testimony

The gemara(סנהדרין ט ב) introduces a debate about testimony. Rav Yosef says that if a witness' testimony also implicates the witness himself in a transgression, then his testimony is invalidated. Rava, on the other hand, argues that, while the witness' testimony cannot be used to convict the witness himself, it is still used to convict his fellow:

ואמר רב יוסף פלוני רבעו לאונסו הוא ואחר מצטרפין להרגו לרצונו רשע הוא והתורה אמרה אל תשת רשע עד רבא אמר אדם קרוב אצל עצמו ואין אדם משים עצמו רשע

The gemara continues with a related teaching of Rava and gives a name to his side of the debate: מפלגינן דיבורא

אמר רבא פלוני בא על אשתי הוא ואחר מצטרפין להורגו אבל לא להורגה מאי קא משמע לן דמפלגינן בדיבורא

Testimony of a Relative or Not Testimony at All

Now let's go back and look at the principle that one cannot incriminate oneself with one's testimony: אדם קרוב אצל עצמו ואין אדם משים עצמו רשע

Rashi sees this halacha as an extension of the general principle that testimony from a blood relative is invalid:

רבא אמר...כלומר על עדות עצמו אינו נעשה רשע שהרי תורה פסלה קרוב לעדות

The Ran (דף י א, ד"ה מהו דתימא), disagrees with this assessment, bringing in the principle of עדות שבטלה מקצתה נתבטלה קולה, that once part of the testimony has been invalidated, all of it is invalidated. Instead, he brings the Raavad's explanation of Rava, which says that the reason the court cannot accept testimony about the witness himself is that it isn't considered testimony at all. As such מפלגינן בדיבורא, into two parts: the inadmissible admission about himself, and the actual testimony about the other which remains valid.

כמו שפי' הרעב"ד... אבל כשהוא מעיד על עצמו, לא שייך ביה תורת עדות כלל, ומ"ה אמרינן אדם קרוב אצל עצמו ופלגינן דיבורה. ולגבי עצמו לא מהימן ולגבי אחר מהימן

In any case, according to both Rashi and the Raavad, testimony is an objective observer's view of the situation. As such one's account about one's own actions are not admissible, either because it is like a relative's testimony, or because it's not considered testimony at all.

Saturday, 16 November 2013

Whether or Not to Encourage a Settlement

The gemara (סנהדרין ו ב) gives four opinions on whether and, if so, when a court should suggest litigants do פשרה/ביצוע:

  1. ר"א בנו של רבי יוסי הגלילי אומר אסור לבצוע
  2. רבי יהושע בן קרחה אומר מצוה לבצוע
  3. רבי שמעון בן מנסיא אומר...עד שלא תשמע דבריהן או משתשמע דבריהן ואי אתה יודע להיכן דין נוטה אתה רשאי לומר להן צאו ובצעו משתשמע דבריהן ואתה יודע להיכן הדין נוטה אי אתה רשאי לומר להן צאו ובצעו
  4. וריש לקיש אמר שנים שבאו לדין אחד רך ואחד קשה עד שלא תשמע דבריהן או משתשמע דבריהן ואי אתה יודע להיכן דין נוטה אתה רשאי לומר להם אין אני נזקק לכם שמא נתחייב חזק ונמצא חזק רודפו...

The Role of the Court

Rav M's class started out looking at the first two opinions, either that Pshara is prohibited, or that it's a mitzva. He attributed the debate to a fundamental dispute over the role of the court:

Mitzva Reason 1: שלום

Rebbe Yehoshua ben Korcha implies his own reason why settlement is a mitzva via two drashot. The gist of both is that, when two sides go to court, they remain enemies even after the ruling. If, however, they manage to come to a compromise, they will leave friends, each having demonstrated that they are willing to compromise for the sake of the other.

Here, the Torah trusts the court with the role not only of passing judgement, but of keeping the peace and preserving society. The judges must look at the big picture and prefer an outcome which, although it conforms less to the value of justice, better upholds the value of keeping the peace.

Prohibition Reason 1: the Role of the Court

Rebbe Elazar son of Rebbe Yosei Haglili also values compromise, as we see from the example he brings of Aharon Hakohen. So why does he forbid the judges from pushing the litigants to settle? Because he thinks the court's role is solely to pass correct judgement, and to uphold society in that manner. Private individuals can encourage the sides to compromise, but once it reaches the judges, they must do their job with no compromises, however well-meaning.

Alternative Reasons to Prefer Settlement

Ultimately, today's halachik courts do prefer פשרה. One of the reasons for this is the limited authority of halachik courts today: they can't judge דיני קנסות because there is no longer smicha and they also don't have authority to use coercive force. The Rav also brought a few more general reasons to prefer pshara:

Mitzva Reason 2: משפט צדק

Contrary to our initial assumption, sometimes settlement yields a more just result than a formal trial. For instance, consider the case of a thief against whom there is not enough evidence(especially given the strict halachik criteria for admissible evidence). If we do פשרה, then at least he will have paid back some of what he owes.

Mitzva Reason 3: Sparing the Judges

Acting as a halachik judge is a great responsibility. The judge is Hashem's representative and is tasked with a near impossible task: to judge a case with imperfect knowledge. The possibility to err is great, so pshara saves the judge from this responsibility by allowing the litigants to reach their own compromise. Rav M quoted a paper by הרב אליהו ליפשיץ(I tried looking it up but couldn't find a reference) that makes this claim, but he challenged it based on our gemara:

רבי חנין אומר לא תכניס דבריך מפני איש ויהו עדים יודעים את מי הן מעידין ולפני מי הן מעידין ומי עתיד ליפרע מהן שנא' (דברים יט, יז) ועמדו שני האנשים אשר להם הריב לפני ה' ויהו הדיינין יודעין את מי הן דנין ולפני מי הן דנין ומי עתיד ליפרע מהן שנא' (תהלים פב, א) אלהים נצב בעדת אל וכן ביהושפט הוא אומר (דברי הימים ב יט, ו) ויאמר אל השופטים ראו מה אתם עושים כי לא לאדם תשפטו כי (אם) לה' שמא יאמר הדיין מה לי בצער הזה ת"ל עמכם בדבר משפט אין לו לדיין אלא מה שעיניו רואות

Rebbe Chanin emphasizes the weighty responsibility of the judge, but then asks why should the judge accept such a heavy responsibility? He answers with a drasha that the judge needs to judge based on what he sees, and not worry about what he doesn't. The gemara seems to be saying that the judge's liability is limited to doing his best with the evidence that is brought before him.

Sunday, 10 November 2013


Last Thursday's class started the topic of פשרה or settlement. Basically, the idea is that, rather than going through the formal process of both sides bringing claims and proofs and arguments in front of the judge and having him decide the case, the litigants come to a compromise on their own.

Strangely, פשרה isn't mentioned in the Mishna at all. Instead, it's main sources are:
  • תוספתא סנהדרין א:ג
  • גמרא סנהדרין ה: למטה עד ו: למעלה


A Type of Litigation or a Private Compromise

The main question the class dealt with was how to define פשרה. On one hand, it may be a way to avoid going through the trouble of the legal process by coming to a private compromise. On the other hand it may itself a type of litigation, albeit a less formal one, in which the litigants agree on a ruling. We saw several debates which seemed to center around this question:

1. Control Over the Process?

There are two stages to arriving at a פשרה:
  1. The compromise itself
  2. The Process i.e. who will judge the case?
Tosafot(ה: ד"ה יפה כח) indicate that the litigants can even choose the judges who will enforce their agreement. This seems to indicate that פשרה is a private agreement, since the process itself is open to negotiation.

The Ran(ה: ד"ה יפה), on the other hand, says that once the compromise itself has been agreed upon, any בית דין can enforce it. This indicates that פשרה is actually a type of litigation, since, as with most litigation, the litigants don't have control over the process.

2. Number of Judges

The gemara(ו א) records a debate as to the number of judges needed for פשרה. Rebbe Meir says 3, while Chachamim say 1:

לימא כתנאי ביצוע בשלשה דברי ר"מ וחכ"א פשרה ביחיד סברוה לכ"ע מקשינן פשרה לדין מאי לאו בהא קמיפלגי דמר סבר דין בשלשה ומר סבר דין בשנים לא דכ"ע דין בשלשה והכא בהא קמיפלגי דמר סבר מקשינן פשרה לדין ומר סבר לא מקשינן פשרה לדין לימא תלתא תנאי בפשרה דמר סבר בשלשה ומר סבר בשנים ומר סבר ביחיד אמר רב אחא בריה דרב איקא ואיתימא רבי יימר בר שלמיא מאן דאמר תרי אפילו חד נמי והאי דקאמר תרי כי היכי דליהוו עליה סהדי אמר רב אשי ש"מ פשרה אינה צריכה קנין דאי סלקא דעתך צריכה קנין למ"ד צריכה תלתא ל"ל תסגי בתרי וליקני מיניה והלכתא פשרה צריכה קנין
Rav M. pointed out that there are two ways to understand this debate. We might read it as a fundamental debate over our issue of how to understand פשרה. If פשרה is a type of litigation, then it is similar to דין and requires 3 judges, just like a normal case. If, however, it is a private agreement, then even a single judge is sufficient.

However, one might also claim that the number of judges isn't subject to our fundamental question about the nature of פשרה. One could understand that both sides of the debate hold that פשרה is a type of litigation, but that חכמים say that since it is a less strict type of litigation so it only requires a single judge.

Rav M. said that while none of the Rishonim say either of these options explicitly, Tosafot Rosh(ד"ה בצוע בשלושה) sounds like he might consider it a fundamental machloket,
ומאן דמחמיר קרי ליה ביצוע שצריך ג' כעין דין שצריך לדקדק ולצמצם ולבצע כפי הראוי מזה וליתן לזה לפי הענין ומאן דמקיל קרי ליה פשרה דאין צריך לדקדק כל כך...
 While the Ran(ד"ה איתיהיה) sounds like he doesn't believe there is a fundamental machloket here:
לפי שדרכו של דין זה מהפך בזכותו של זה וזה מהפך בזכותי של זה מפני שאינן לשלום אלא כעין מלחמה, אבל פשרה שהיא שלום ושניהם מתכוונים בו האחד בשניים...

3. How carefully do we do פשרה?

Another possible difference borrowed from the Tosafot Rosh above is how carefully we do פשרה. The Tosafot Rosh says that according to Rebbe Meir פשרה requires the judges to be just as careful about weighing each side's case as in an official trial. This makes more sense if we assume that פשרה is actually a type of litigation. On the other hand, if it's a private compromise then there's no need for so much formal process and it's more important to get the sides to agree to some compromise.

4. Is a Kinyan Required?

The gemara above brings Rav Ashi's conclusion that if Pshara requires 3 judges, there is no need for a kinyan. The implication is that according to Chachamim who require only 1 judge, we do need a kinyan to make the settlement official. The Ohr Zaruah reads the gemara like this and the implication again seems to be that if פשרה is a private agreement then it requires a kinyan like any private contract, while if it is a type of litigation so the judges authority is what makes it official.

It's worth noting that Rashi reads the gemara's conclusion differently:

והלכתא פשרה צריכה קנין: ואפילו נעשית בשלשה

Surprisingly, Rashi reads the Gemara's conclusion as saying that according to both opinions a kinyan is required. Tosfos(ד"ה והלכתא) explains, however, that this is for an external reason, so that the litigants won't be able to overturn the פשרה by claiming the judges weren't knowledgeable enough.

Monday, 4 November 2013

Those Extra Parts in Shema

So, at some point I acquired the understanding that the main parts of Kriyat Shema are the first line, then there's the fluff in the middle, and then the last line is a separate mitzva of Remembering the Exodus. It's sort of a strange understanding--that Shema contains 3 paragraphs of "filler" in the middle, but it didn't bother me too much. Until now, when I heard a better explanation.

Rav Soloveichik begins his שעורים לזכר אבי מרי ז"ל with two classes about Kriyat Shema:
  • מצות קריאת שמע וזכירת יציאת מצרים
  • שיעור קריאת שמע מן התורה

These essays are well worth reading in full, containing an in-depth analysis of the source, meaning, and dinim of Kriyat Shema, but I want to focus on one of the main conclusions about why we read the various paragraphs of Shema. The Rav describes the entirety of kriyat shema as a חפצה של קבלת עול מלכות שמים and also proposes that the separate mitzva of Remembering the Exodus is actually an essential part of the mitzva of kriyat shema and a philosophical basis for said קבלת עול. In addition, the Rav lists the major themes prevalent throughout Kriyat Shema. Let's go over his list and how they each apply to קבלת עול מלכות שמים.

1. יחוד

A monotheism creed: God is the one, there is no other. Thus we are dedicated to him alone.

Alternatively, a statement of God's all encompassing nature. Because of his central importance in all Existence, we accept the yoke of his commandments.

שְׁמַע יִשְׂרָאֵל יְהוָה אֱלֹהֵינוּ יְהוָה אֶחָד.

2. אהבה

We love God and therefore we keep his commandments.

וְאָהַבְתָּ אֵת יְהוָה אֱלֹהֶיךָ, בְּכָל-לְבָבְךָ וּבְכָל-נַפְשְׁךָ וּבְכָל-מְאֹדֶךָ. וְהָיוּ הַדְּבָרִים הָאֵלֶּה, אֲשֶׁר אָנֹכִי מְצַוְּךָ הַיּוֹם--עַל-לְבָבֶךָ.


3. תלמוד

Accepting the yoke of God's commandments has a corollary: we must learn them in order to keep them.

וְשִׁנַּנְתָּם לְבָנֶיךָ וְדִבַּרְתָּ בָּם, בְּשִׁבְתְּךָ בְּבֵיתֶךָ וּבְלֶכְתְּךָ בַדֶּרֶךְ, וּבְשָׁכְבְּךָ וּבְקוּמֶךָ. וּקְשַׁרְתָּם לְאוֹת עַל-יָדֶךָ; וְהָיוּ לְטֹטָפֹת בֵּין עֵינֶיךָ. וּכְתַבְתָּם עַל-מְזֻזוֹת בֵּיתֶךָ, וּבִשְׁעָרֶיךָ. 


4. עול מצות

The main expression of our commitment to do God's will is in the Mitzvot. That is the primary method God has chosen to instruct us in his will.

וְהָיָה אִם-שָׁמֹעַ תִּשְׁמְעוּ אֶל-מִצְו‍ֹתַי, אֲשֶׁר אָנֹכִי מְצַוֶּה אֶתְכֶם הַיּוֹם--לְאַהֲבָה אֶת-יְהוָה אֱלֹהֵיכֶם, וּלְעָבְדוֹ בְּכָל-לְבַבְכֶם וּבְכָל-נַפְשְׁכֶם. וְנָתַתִּי מְטַר-אַרְצְכֶם בְּעִתּוֹ, יוֹרֶה וּמַלְקוֹשׁ; וְאָסַפְתָּ דְגָנֶךָ וְתִירֹשְׁךָ וְיִצְהָרֶךָ. וְנָתַתִּי עֵשֶׂב בְּשָׂדְךָ לִבְהֶמְתֶּךָ; וְאָכַלְתָּ וְשָׂבָעְתָּ. הִשָּׁמְרוּ לָכֶם, פֶּן יִפְתֶּה לְבַבְכֶם; וְסַרְתֶּם וַעֲבַדְתֶּם אֱלֹהִים אֲחֵרִים, וְהִשְׁתַּחֲוִיתֶם לָהֶם. וְחָרָה אַף-יְהוָה בָּכֶם, וְעָצַר אֶת-הַשָּׁמַיִם וְלֹא-יִהְיֶה מָטָר, וְהָאֲדָמָה לֹא תִתֵּן אֶת-יְבוּלָהּ; וַאֲבַדְתֶּם מְהֵרָה מֵעַל הָאָרֶץ הַטֹּבָה אֲשֶׁר יְהוָה נֹתֵן לָכֶם. וְשַׂמְתֶּם אֶת-דְּבָרַי אֵלֶּה עַל-לְבַבְכֶם וְעַל-נַפְשְׁכֶם; וּקְשַׁרְתֶּם אֹתָם לְאוֹת עַל-יֶדְכֶם, וְהָיוּ לְטוֹטָפֹת בֵּין עֵינֵיכֶם. וְלִמַּדְתֶּם אֹתָם אֶת-בְּנֵיכֶם לְדַבֵּר בָּם, בְּשִׁבְתְּךָ בְּבֵיתֶךָ וּבְלֶכְתְּךָ בַדֶּרֶךְ, וּבְשָׁכְבְּךָ וּבְקוּמֶךָ. וּכְתַבְתָּם עַל-מְזוּזוֹת בֵּיתֶךָ, וּבִשְׁעָרֶיךָ. לְמַעַן יִרְבּוּ יְמֵיכֶם וִימֵי בְנֵיכֶם, עַל הָאֲדָמָה אֲשֶׁר נִשְׁבַּע יְהוָה לַאֲבֹתֵיכֶם לָתֵת לָהֶם--כִּימֵי הַשָּׁמַיִם עַל-הָאָרֶץ.

5. ציצית

Similar the previous section. The specific mitzva of Tzitzis is seen as a symbol and a reminder to keep all the Mitzvot.

וַיֹּאמֶר יְהוָה אֶל-מֹשֶׁה לֵּאמֹר. דַּבֵּר אֶל-בְּנֵי יִשְׂרָאֵל וְאָמַרְתָּ אֲלֵהֶם וְעָשׂוּ לָהֶם צִיצִת עַל-כַּנְפֵי בִגְדֵיהֶם לְדֹרֹתָם וְנָתְנוּ עַל-צִיצִת הַכָּנָף פְּתִיל תְּכֵלֶת. וְהָיָה לָכֶם לְצִיצִת וּרְאִיתֶם אֹתוֹ וּזְכַרְתֶּם אֶת-כָּל-מִצְו‍ֹת יְהוָה וַעֲשִׂיתֶם אֹתָם וְלֹא-תָתוּרוּ אַחֲרֵי לְבַבְכֶם וְאַחֲרֵי עֵינֵיכֶם אֲשֶׁר-אַתֶּם זֹנִים אַחֲרֵיהֶם. לְמַעַן תִּזְכְּרוּ וַעֲשִׂיתֶם אֶת-כָּל-מִצְו‍ֹתָי וִהְיִיתֶם קְדֹשִׁים לֵאלֹהֵיכֶם.

6. יציאת מצרים

When God took us out of slavery in Egypt, we became obligated to him.

 אֲנִי יְהוָה אֱלֹהֵיכֶם אֲשֶׁר הוֹצֵאתִי אֶתְכֶם מֵאֶרֶץ מִצְרַיִם לִהְיוֹת לָכֶם לֵאלֹהִים, אֲנִי יְהוָה אֱלֹהֵיכֶם.

Saturday, 2 November 2013

Permission to Judge, Permission to Teach

So we discussed two types of permission a sage requires to do his job in Rav M's class today. The first is permission to act as a Judge in monetary cases, while the second is permission to teach practical Halacha.

Torah Judgement vs. Kingly Judgement

The King as Judge
What's the issue? This is how I understood it, keeping in mind that I missed a few classes: Today we don't have smicha going back to Moshe Rabeinu, so how can a sage act as a judge in a monetary case? There is another track to acting as Judge: the track of a King. A king from the tribe of Judah has the divine right to rule over Israel and this is independent of smicha. So the King's right to judge is not based on his Torah knowledge as with smicha, it's based on his right to rulership.

Permission to Judge

Now, in the time of the Gemara there was no king, but there were the נשיא and the ריש גלותא and their right to rule the community in exile is based on that of the King. So, their ability to pass judgement in monetary cases is based not on their being a representative of Torah law per say, but on the principle of הפקר בית דין הפקר, basically that the King has the right to decide to take away your property when appropriate. That's where the issue of permission comes in. If only the נשיא and the ריש גלותא have the right to judge monetary cases, then any sage who wants to judge a monetary case must do so with their permission, basically as their representative.

So today's discussion revolved around the following gemara on Sanhedrin 5A:

והא רבה בר רב הונא כי הוה מינצי בהדי דבי ריש גלותא אמר לאו מינייכו נקיטנא רשותא נקיטנא רשותא מאבא מרי ואבא מרי מרב ורב מר' חייא ור' חייא מרבי

The problem is that Raba Bar Rav Huna lived after Rebbe, so how can his permission still hold power after his lifetime? Tosfos(ד"ה נקיטנא) says it works like smicha i.e. it can be passed on to future generations, but it's not so clear why that should be. The Rivash(סימן רעא) says that it's a girsa mistake and really it's an earlier amora, Raba Bar Bar Chana, which makes more sense, although the Ohr Samachach disputes this on textual grounds i.e. that Tosfos' girsa is correct, however hard it is to understand.

Permission to Teach

סמיכת יהושע בן נון

The second part of the class dealt with permission to teach halacha, discussed on Sanhedrin 5B. There are a couple factors at play here. First off, the gemara says that Chazal realized that, with the absence of smicha, there needed to be a minimum standard for teaching halacha, otherwise mistakes would occur.

באותה שעה גזרו תלמיד אל יורה אלא אם כן נוטל רשות מרבו

Additionally the gemara brings a baraita saying that a student shouldn't teach in the proximity of his master.

ותניא תלמיד אל יורה הלכה במקום רבו אלא אם כן היה רחוק ממנו שלש פרסאות כנגד מחנה ישראל

And finally, the rishonim point out another gemara(עירובין סג א) that seems to indicate that a student shouldn't teach in the lifetime of his master regardless of the distance.

אמר רבא בפניו אסור וחייב מיתה שלא בפניו אסור ואין חייב מיתה

So how do we resolve this contradiction?

Tosafot(ד"ה אלא) say that our gemara is talking about where the teacher gave permission to teach and the gemara in Eruvin is where the teacher didn't give permission to teach. But the question then arises, why can't the Rebbe be מוחל על כבודו as with other mitzvas of  כבוד הרב?

כבוד הרב לאומת כבוד המסורת עצמה

The answer seems to be to distinguish between the personal honor of the Rebbe vs. the Honor of the Tradition. Teaching in close proximity to one's teacher doesn't just damage his honor, the lack of deference is viewed as an assault on the mesoret itself and therefore the Rebbe cannot be מוחל.

The Ran brings the opinion of Rabeinu David, who says like Tosafot, but the Ran doesn't understand why the Rebbe can't be מוחל.

The Rambam takes a different approach, essentially saying that our gemara is talking about answering an occasional halachik question vs. opening one's own competing beit midrash. The former is allowed when far from the Rav or in close proximity with the Rav's permission. The latter is never allowed, again, presumably because it's an issue of the honor of the mesoret itself, not just the personal honor of the Master.