Shiur Sukkah 43b 09/10/22 – Final Shiur of 5782

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Sukkah 43b 

Elul 24, 5782. September 20, 2022

1- We continued our Gemara that discusses the Mitzvah of ערבה (what we call הושענות) in the בית המקדש and the Minhag that was enacted זכר לחורבן. 

willow branches with leaves isolated on a white background. vertical photo.

2 – We highlighted the interesting statement of the Gemara about ערבה:

עֲרָבָה שִׁבְעָה. כֵּיצַד? עֲרָבָה בִּשְׁבִיעִי מַאי טַעְמָא דָּחֲיָא שַׁבָּת? אָמַר רַבִּי יוֹחָנָן: כְּדֵי לְפַרְסְמָהּ שֶׁהִיא מִן הַתּוֹרָה.

Set of Hoshanos — Mitzvahland.com

Something that is not mentioned explicitly in the Torah, like ערבה, was granted importance to counter the בייסותים

ערבה, being that it’s an הלכה למשה מסיני, a Mitzvah the בייסותים denied, was allowed to be observed on Shabbos, as opposed to Lulav. 

מצוות הושענה במקדש

What is amazing is that after the Churban, when the ערבה Minhag was instituted זכר למקדש, the set calendar which Hillel created, ensures that הושענא רבה never occurs on a Shabbos. 

But why didn’t he ensure that Rosh Hashanah does not fall on on Shabbos? Or the first day of Sukkos where Lulav, like Shofar, is a מצות עשה מן התורה?

Jewish Calendar - Judaism 101 (JewFAQ)

The answer is as above, the help perpetuate the מסורה, the Chachamim gave the Minhagim ‘more importance’ that even a מצוה דאורייתא. 

Other ראשונים say the reason is that Shofar and Lulav, if not observed on Shabbos,  can at least be at be observed the next day, on Sunday. 

ערבה, on the other hand, if הושענא רבה occurs on Shabbos, we cannot do it on שמיני עצרת because it would ‘embarras’ שמיני עצרת. 

Hoshana Rabbah - Sukkot & Simchat Torah

3 – In regards to the amount of Hadasim one should place in the Lulav, we reread the few lines on Daf 34b. Where it states:

׳ תַּנְיָא, רַבִּי יִשְׁמָעֵאל אוֹמֵר: ״פְּרִי עֵץ הָדָר״ — אֶחָד. ״כַּפֹּת תְּמָרִים״ — אֶחָד. ״עֲנַף עֵץ עָבוֹת״ — שְׁלֹשָׁה. ״עַרְבֵי נַחַל״ — שְׁתַּיִם.

From this it would seem that there is an exact number to use. 

No more than 1 Lulav, 1 Esrog, 2 Arovos and no more than 3 Hadassim. However, it’s not so simple. 

Alef (mehudar) Hadassim – Esrogim

No one uses more than 2 ערבות. If one cannot add ערבות why could one add הדסים? 

Here is what the Rambam says Lulav 7,7: 

  • כַּמָּה נוֹטֵל מֵהֶן. 
  • לוּלָב אֶחָד וְאֶתְרוֹג אֶחָד וּשְׁנֵי בַּדֵּי עֲרָבָה וּשְׁלֹשָׁה בַּדֵּי הֲדַס. 
  • וְאִם רָצָה לְהוֹסִיף בַּהֲדַס כְּדֵי שֶׁתִּהְיֶה אֲגֻדָּה גְּדוֹלָה מוֹסִיף. וְנוֹיֵי מִצְוָה הוּא. 
  • אֲבָל שְׁאָר הַמִּינִין אֵין מוֹסִיפִין עַל מִנְיָנָם וְאֵין גּוֹרְעִין מֵהֶן. 
  • וְאִם הוֹסִיף אוֹ גָּרַע (פָּסוּל):

Rabbi Ash - Arba'a Minim

He allows more Hadasim but not more Aravos. Can we assume that adding more Aravos will not add to the נוֹיֵי מִצְוָה?

Where is his source that if one adds more ערבות it is פסול? 

The Kesef Mishneh writes that the חכמים of the Provence in France wrote that the Rambam late in his life changed his mind and ruled that adding more than 2 ערבות is כשר. Hence the word פסול is printed in parentheses. Additionally, the Rambam writes that in the Gemara there is a source for adding more הדסים. Where in the Gemara however, remains a mystery. 

What Is Sukkot? - A Guide to The Jewish Holiday of Sukkot, The Feast of Tabernacles, and the Meanings Behind it - Sukkot & Simchat Torah

4 – We discussed if the circling around the בימה with the Lulav in a counterclockwise direction is intentional. In the Southern Hemisphere do they do it in reverse?…..

Can somebody finally settle this question: Does water flowing down a drainspin in different directions depending on which hemisphere you're in? And ifso, why? - Scientific American

Story of Reb Meir Aurbach who suspected that a witness, who claimed to have have been present at divorce overseas, was not being truthful. 

He casually asked him if he remembers when the wife, during the Get procedure, circled her husband (to undo the circling under the Chuppa at the   קידושין) if it was in a direction opposite to the one that was dohne when they got married….. 

The witness said, indeed it was the opposite direction….

Gotcha - Highfield Primary School

5- We discussed the Mitzvah of ביכורים and the question of the Alshich. The trip to ירושלים with the first fruit was a festive occasion and procession as elaborated in Mishnayos Bikurim. Now one can understand if a farmer with many acres of produce makes this time consuming trip hauling up the first fruit from every tree. He may even need a 20’ truck. 

However, for those less fortunate with just one or two trees…. how can we expect him to ‘close shop’ for a few weeks (if he lived in the Golan) and make the trip? His entire  הבאת ביכורים of one Rimon and one date fit into his pocket! 

Bringing Bikurim | Arte judío, Costumbres judias, Arte biblico

The Alshich answer at length that the Torah expects one to show thanks and appreciation for the ‘small’ gifts we receive from above. 

The דרשנים add, based on the Midrash that at the conclusion of the ceremony of the bringing the ביכורים one would hear a בת קול- see you next year. תזכה לשנה הבאה. 

That promise of דער לעב איבער א  יאר was enough to entice even small farmers to make the trip. 

שפת אמת ליקוטים פ’ תבוא.

במדרש תנחומא בת קול יוצאת תשנה לשנה הבאה. לכאורה תמוה דאם כך לא מת אדם מעולם דודאי נתקיים הבת קול אם כן לעולם יחיה האדם. ויש לומר כי הבת קול היתה רק אחר הקריאה. וגם אי הביא בלא קריאה כגון מחג ואילך מכל מקום נתקיים בזה הבת קול אם כן שפיר משכחת להיות נפסק הבת קול בשנה אחת. עוד יש לומר כי הבת קול היתה בשכר הבאת הביכורים אם כן יש לומר דלעולם היה הבת קול נפסק שנה שניה כיון דהביא בכח גזרת הבת קול דשנה ראשונה אם כן נפסק בשנה שניה רק בשלישית שהביא מעצמו שוב היתה הבת קול וכן לעולם

ואומרים בשם הפני מנחם שאולי נפטרו בשנה שאחרי שמיטה שלא הביאו

ביכורים ועד”ז הי’ בחורבן הבית

שהי’ במוצאי שביעית

Do we receive this בת קול today? 

Perhaps. 

The Gemara (BB 12b) states that when the Beis Hamikdash was destroyed נבואה was given to children and שוטים. In comparison to previous generation we can humbly admit that we fit that category…..

So perhaps that is the source of the Minhag to wish each other לשנה טובה תכתב ותחתם….

A Gut Yor to all. 

שנה טובה ומתוקה • רדיו חיפה 107.5

Shiur Sukkah 43a (2) 09/13/22

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Sukkah 43a (2)  

Elul 17, 5782. September 13, 2022

1- We continued the topic of someone doing a Mitzvah when the Chachamim enacted a גזירה not to do it. Such as blowing the Shofar on Shabbos. Was a Mitzvah performed? Or perhaps, since there is a גזירה not to do it, he did nothing. 

File:JEWISH MAN BLOWING THE SHOFAR.JPG - Wikimedia Commons

 

The difference would be for example if someone forgets it’s Shabbos, makes a Brachah and then realizes that it’s Shabbos. If there (still) is a Mitzvah (despite the prohibition to do it) then he must continue to blow the Shofar, for if not, it would cause his ברכה to be לבטלה. On the other hand, if the Mitzvah was totally uprooted then he cannot continue to blow the Shofar, due to the גזירה , for it has no ‘value’. 

2- We mentioned the Tosfos on 3a (Shiur on 3a)  where they explicitly say that if the Chachamim prohibit something, doing it is worthless. 

Example: A tight fitting Sukkah on a fire escape. Not having much room to maneuver one wants to place his plate on the windowsill which is out of the Sukkah. The issue is one may lean over the plate and eat outside the Sukkah. So the Chachamin enacted a גזירה never to place the plate on the window sill. 

If someone does do it and eats from the plate carefully and makes sure his body is still in the Sukkah – מן התורה he is יוצא. However מדרבנן he is not. Comes Tosfos and says that due to the גזירה he is not יוצא מן התורה ! Meaning that on night #1 of Sukkos he would need to eat another meal in a Sukkah. 

We discussed the difference between this case and blowing Shofar on Shabbos.      

3- We mentioned last week Reb Akiva Shleizinger who wanted to introduce Shofar blowing on Shabbos in a Beis Din. 

Blowing of the Shofar During Elul - YouTube

Reb Akiva (who was named after Reb Akiva Eiger) also ruled that one who makes Aliya to Israel and his wife refuses to go along, he may marry another women despite the חרם דרבינו גרשום!!

See here

In the book “Beit Yosef Hadash” he wrote that in the event that a man from Israel immigrates to Eretz Israel and his wife does not agree to accompany him – he is allowed to marry a second woman in Eretz Israel, despite the boycott of Rabbeinu Gershom. Jerusalem readers revolted against him and declared a boycott. All members of the Hungarian kollel had to sign their consent to the boycott either on a letter sent abroad or when they came to receive the “distribution” allowance. A record was on the table and everyone was “asked” to sign before receiving the money. Only a few withstood this pressure. Among them were Joshua Stampfer and Rabbi Menachem Manish Scheinberger, Rabbi Schlesinger’s colleagues. Rabbi Menachem Manish even beat the table with his fist until the “letter” flew from the table and he shouted “Tzelem He’emido Al HaShulchan HaZeh, Vayishtachavu Lo Kulam Avur Kesef Nim’as!”. Of course he was prevented from receiving money from the distribution and his relatives had to send money for his family’s livelihood. As a result of this conflict, the book was published with a booklet Shimru Mishpat warning against the claims of the Hungarian Kollel. In response the booklets Nitotz HaBayit and Shomer Yisrael were published. Rabbis even ruled that Rabbi Schlesinger’s books were not to be genizahed but burned according to the law of minim and heretics, but despite that, upon his death Rabbi Yosef Haim Zonenfeld accorded him respect, and eulogized him.

Burning Books? Let's Confront The Real Issue. | Gwyn

4-  מכשירי מצוה. The Gemara brings the opinion of Reb Eliezer that allows one to do a מלאכה on Shabbos in the preparation to perform the מצווה of the ד’ מינים. 

What Happens When You Cut The Pop Off a Palm Tree? (...2 min read)

As Rashi writes: ‘(Reb Eliezer allows one) to cut off from the place of its attachment’. Meaning that Reb Eliezer allows one to cut the ד’ מינים off the the tree on Shabbos/Yom Tov. He would also allow the burning wood to create coal to form a knife for the purpose of a ברית. 

Island Blacksmith: How a knife is made from reclaimed and natural materials using traditional techniques

Does Rashi mean to imply that the ד’ מינים are פסול when attached to the ground? We mentioed the פרי מגדים and others that discuss this. 

See Shiur 32a

5- Speaking of a ברית we mentioned the amazing story of Reb Peretz Mochkin A”H who traveled once from Tashkent to Smarkand when their car broke down. Waiting in a small remote village for it to be repaired he was approached by a Jewish woman (who was a refugee from Poland) asking them if he can perform a Bris on her newborn that was 30 days old. Reb Peretz managed to get the necessary tools to perform the Bris and the פדיון הבן was done as well!  

Rabbi Peretz Mochkin.

R.  Peretz Mochkin

6 – We spoke about the rare print of the  סידור of the Alter Rebbe that was discovered in Russia a few years ago. See here for a reprinting of that rare edition. Its discovery created a buzz among many researchers and various analyzations of that particular edition have been published. The comparison, to the other printed editions we have, has provided a greater understanding on the uniqueness of the Alter Rebbe’s נוסח . 

קובץ:תפילות מכל השנה.jpg

One of the differences: 

In our Siddur:- .אשמנו. בגדנו. גזלנו. דברנו דופי

Means  we have spoken slander  דברנו דופי

This unique edition has it as – .אשמנו. בגדנו. גזלנו. דברנו. דופי

The extra dot seems to say that דברנו in itself as something negative. It is not associated with דופי – slander. Just speaking is something negative for which we ask forgiveness.  

[Then there is דברנו דופי to slander] 

Is the extra dot a typo? What is wrong with just speaking?? 

Reb Yoel Kahan A”H once suggested (half jokingly) that it is not typo at all. 

Speaking without purpose is equally not proper. As he put it, using a Yiddish uncommon word,  פלוידערון. To just blabble. 

דברנו.

7- In conclusion we touched upon the topic if there was a Sukkah in the Beis Hamikdash. To be continued. 

Bais Hamikdash- Blue and Gold Series | Nechama Fine ArtKVT

 

Shiur Sukkah 43a 09/06/2022

BS”D

Sukkah 43a 

Elul 10, 5782. September 6, 2022

1- We discussed the famous גזירה דרבה which the Chachamim enacted not to perform certain mitzvos, such as לולב and תקיעת שופר, when יום טוב falls out on Shabbos. The concern was that one may unintentionally carry it 4 Amos in a  רשות הרבים. Why would one do it? To visit a בקי – knowledgeable person – to teach him how to perform this particular Mitzva. 

How the Shofar is used on Shabbat - The Jerusalem Post

It is a peculiar גזירה indeed as the Alter Rebbe (LT 56,1) writes that such lofty Mitzvos as Shofar and Lulav were canceled because of ‘simpletons and small minded individuals’ that may carry out the Shofar or Lulav. 

 

Uprooted tree, artwork - Stock Image - F010/5971 - Science Photo Library

Uprooting a mitzva?

 עוד יש לעורר ולשום לב מה ראו חז”ל לעקור מ”ע דשופר ולולב אפילו ביום ראשון בגבולין עכ”פ אפילו בזמן שאין בהמ”ק משום גזרה דרבה בעלמא והלא החשש הוא להדיוטים וקלי הדעת ואיך מנעו המצוה לגמרי מכמה צדיקים גדולים וטובים ובפרט מצות שופר ולולב שהרבה כוונות תלויות בהם ליודעי דעת שנוגעים עד רום המעלות.

2- This is a famous Sugyah and we touched upon some points. 

a – Why מעביר ד’ אמות ברשות הרבים? Why not be concerned about the עקירה והנחה; when he leaves the house and arrives at the house of the בקי? 

b – While it may be an art to blow Shofar it is relatively easy to perform the ד’ מינים Mitzvah. So simple and easy that the גמרא earlier had an issue of finding a case of one walking out of his house holding the ד’ מינים and not being יוצא. “He was יוצא by just picking it up”  – even if the Lulav is not bound at all. 

Rabbi Levi Meisner Gives Brooklyn Shofar Lessons - The New York Times

Shofar Expert

So what can the בקי teach him? 

Rashi writes that he goes to the בקי to learn the נענועים and ברכה. We mentioned that perhaps ‘learning the ברכה’ is not the ברכה itself, which is quite simple. It means as to when to make the ברכה as we discussed the four solution of Tosfos on how to ensure that the ברכה is made prior to being יוצא. Such as flipping it etc. See Shiur 39a. 

c – We learnt a few pages earlier that if one does walk out with his Shofar or Lulav to רשות הרבים on Shabbos he is פטור because he is טעה בדבר מצווה. So what’s the issue here to cancel such important Mitzvos when there is never a חיוב חטאת anyway? 

d-  Why is this גזירה not applied to מילה on Shabbos, blowing the Shofar מוצאי יום כיפור before Havdalah?  We mentioned the Tosfos in Megillah 4a that answers these two Mitzvos. What about קריאת התורה? That one really needs help from a בקי

 

3- We discussed the issue of Matzah that is still observed on Shabbos. Why aren’t the complexities of the Seder in general and of the כזית Matzah in particular enough to cause someone to walk to the בקי for exact instructions? 

[Story of the fellow that got stuck by  יחץ…..…and sent his wife to observe the בקי from the window….]

5,392 Peeking Window Stock Photos, Pictures & Royalty-Free Images - iStock

 

We mentioned the many answers to this question. Here is a link to dozens of them. 

4- We discussed the famous Sichah of the Rebbe, LS 6, 48, on this topic.  

Briefly – the Rebbe first quotes a few answers – we labeled them as a Litvishe answer and the other a Poilisher one. 

The Litvishe from the Netziv : The בקיאים would roam at the homes of the lesser learned to instruct on how to perform the סדר. 

[Wow! A Litvisher Godol suggesting 150 years ago for Shulichim to travel to perform Sedorim for the less informed….]

The Rebbe’s question on this answer: This מנהג in nowhere mentioned. 

Another answer from the Netziv: Matzah is observed at night when people refrain from roaming the streets. 

The Rebbe’s question on this answer: Despite the danger, the average Jew will ignore the danger to fulfill the Mitzvah of Matzah. Especially since it’s ליל שימורים. 

The Poilisher style answer from Reb Don Polotzki: Although the חכמים canceled the Mitzva of Shofar and Lulav, this cancelation only applied to part of the Mitzvah. How? By learning the הלכות of Shofar and Lulav it is ‘considered as if he actually performed it’

כל העוסק בתורת עולה כאילו הקריב עולה.

 So on יום טוב שחל להיות בשבת, by learning the Halachos, the Mitzvah is not totally canceled. Part of it is still ‘performed’. 

Learn Chassidus: Lessons in Torah Or & Likutay Torah

That is all good and well with Shofar and Lulav, when by learning about them Part of the Mitzvah remains. 

In regards to Matzah that would be problematic as women are also  חייב to eat Matzah but their learning the הלכות will not do much since they are פטור from תלמוד תורה!  

פוילישער style indeed! 

Rabbi Don Polotzki

The Rebbe’s question on this answer: There is no mention anywhere the obligation to sit down on Rosh Hashana or Sukos  שחל להיות בשבת and learn the Halachos of these Mitzvos. 

 

In regards to Megilah see the Sichah above. 

The Rebbe’s answer על פי חסידות: From the fact that the גזירה was enacted at a certain time in history it is evident that any רוחניות effect that was previously accomplished by תקיעת שופר and לולב is no longer needed. Meaning that Shabbos will accomplish now (as opposed to the era prior to גזירה דרבה) whatever the Shofar or Lulav accomplished before the גזירה. 

 

Shabbat Candlesticks Painting Shabbos Candle Lighting - Etsy

 

 

However with מצה, since שבת for whatever reason, will not accomplish what the eating of the מצה would do, there cannot be a גזירה to cancel this Mitzvah and as a consequence no one will ever take his מצה  and be מעביר ד’ אמות ברשות הרבים. 

See the Sichah at length. 

5- So no Shofar blowing on Shabbos and no Lulav shaking on Shabbos. 

 

 

What happens if one did do it? Did he do a Mitzvah and should not say שהחיינו the next day? [Question is in places that have only one day יום טוב] or perhaps he did ‘nothing’? 

 

6- Regarding Shofar the Gemara says that an established Beis Din does indeed blow the Shofar on Shabbos within its confines. 

We discussed the story of Reb Akiva Shleizinger (an interesting Rov – more next week) who wanted to establish this Beis Din מנהג in 1905. He planned a gathering of many Rabanim at the Churva Shul and actually blew the Shofar on Shabbos. 

Churva Synagogue

Rumor had it that despite the opposition to his initiative (which failed to materialize) he did it in the confines of his own house! 

7- We mentioned an interstinhg historical fact -that ראש השנה  in 1905 corresponded to the exact date that the Rebbe Rashab began his famous multi year המשך of ראש השנה שחל להיות בשבת תרס”ו that began on ראש השנה, year 5666, September 29, 1905 explaining why there is no need to blow the shofar on Shabbos!

 

Shiur Sukkah 42a (3) 42b 08/30/22 Siyum

BSD 

Suka 42a (3) /  42b

Elul 3, 5782. August 30, 2022 

We continued learning the Breisah that enumerates the Mitzvos a קטן needs to do prior to Bar Mitzva. 

1- 

 תָּנוּ רַבָּנַן:

 קָטָן הַיּוֹדֵעַ לְנַעְנֵעַ — חַיָּיב בְּלוּלָב. It doesn’t say that the father needs to purchase him a Lulav, 

We discussed this point last week as to why the Shulchan Aruch adds the words קטן היודע לנענע לולב כדינו אביו חייב לקנות לו לולב כדי לחנכו . 

tzitzis – RabbiKaganoff.com

2- לְהִתְעַטֵּף — חַיָּיב בְּצִיצִית

We discussed: 

a-the Tosfos in Erchin 2b that says that there is no reason for the father to purchase ציצית  for him since the child has his own בגד and what is needed is the father to add the ציצית strings. 

Jewish Children.com

b-  the wording להתעטף, meaning to wrap. We spoke about this topic at the beginning of Suka 3a. The opinion of the Geonim that from the ברכה – להתעטף  we see that only a בגד that fully wraps the body, front and back is חייב בציצית. 

The Yemenite Jews | Ethnographic materials ML.

ה יש אומריםיח מדתקנו חז”ליט לברך להתעטף בציצית מכלל דהמצוה היא להתעטף דוקא וכל עטיפה שאינה כעטיפת הישמעאלים אינה נקראת עטיפה אלא לבישהכ ולכן צריך להתעטף בטליתו כעטיפת הישמעאלים דהיינו לכסות הראש עם הפנים עד גומות שבלחי למטה מפיוכא ולדבריהם טליתות קטנות שלנו שאין בהם עטיפת הראש פטורים מציצית לגמריכב:

How to Put On a Tallit - Synagogue How-To - Video

The Halacha follows the ראשונים that disagree and say that any four cornered garment if חייב בציצית. The reason the ברכה is worded with להתעטף is simply because at that time most people wore their garments as shawls that warped around them.

 ו אבל יש אומרים כג שכל כסות של ד’ כנפות אע”פ שאין בה עיטוף חייבת בציצית שהרי נאמר בתורה כד על כנפי בגדיהם וכל מלבוש ובגד במשמע והעיטוף אין לו אפילו רמז בתורה כלל כה ומה שתקנו חכמים לברך להתעטף בציצית היינו לפי שהיה מנהגם לעטוף ראשם בטליתםכו ואף בימיהם לא היו מתעטפין כעטיפת הישמעאלים אלא כדרך בני אדם שמתעטפין בכסותם ועוסקין במלאכתםכז פעם בכיסוי הראש ופעם בגילוי הראש לכן אף אנחנו אף שאנו מברכין להתעטף בציצית אין אנו צריכין יותר והלכה כסברא הב’כח. ומכל מקום כדי לקיים מצות ציצית מן המובחרכט נכון הדבר להתעטף כעטיפת הישמעאלים בשעת ברכהל ויעמוד כך כדי הילוך ד’ אמות ובזה יוצא אף לסברא הראשונה דעיקר הקפידא היא בשעת לבישה לא דהא אם היה רוצה היה מסירה ממנו לגמרי אחר כך:

   3- לִשְׁמוֹר תְּפִילִּין — אָבִיו לוֹקֵחַ לוֹ תְּפִילִּין. 

Young religious Jewish boy puts on phylacteries - tefillin - for the first time at a synagogue in Brooklyn, New York Stock Photo - Alamy

Change of wording here. לקיחה versus חייב. The father needs to buy him a pair of Tefillin. Why not just say חייב and he can use his father’s תפילין?

a- We discussed the reason for the need to purchase for him תפילין (as opposed to ציצית) as the above Tosfos explains since a child does not have his own תפילין the father needs to purchase for him a new pair. Another reason is that תפילין being expensive the word לקיחה is more appropriate. 

b – A brilliant explanation from the פרדס יוסף

The issue with the קשר of Tefillin. It’s a big topic – briefly, רבינו אליהו , a ראשון, says when the Torah says וקשרתם, it means literally  – to tie it!  One needs to untie the entire knot every day at the conclusion of the מצווה and making a totally new knot the next morning. 

Are My Tefillin (Still) Kosher?

Most ראשונים argue, saying that since  תפילין need a קשר של קיימא (otherwise it’s not considered a knot but a bow) untying and tying it every day makes this knot not a permanent knot but a temporary one. 

As we see in regards to שבת , a knot that is untied every day is not really considered a knot. It’s not a קשר של קיימא. So one should absolutely not undo the knot every day! 

הלכות שבת - מלאכת קושר ומתיר - מוקד תהילים ארצי

Obviously the וקשרתם means (not to tie the knot daily) but to bind it to your hand! See Tosfos Menochos 35b

So, suggests the פרדס יוסף, if a child would use his father’s תפילין it’s likely that they would need to adjust the knot on a daily basis. That would be a problem according to most ראשונים.
Thus the need to purchase for a son a new pair of Tefillin.לִשְׁמוֹר תְּפִילִּין — אָבִיו לוֹקֵחַ לוֹ תְּפִילִּין

4-יוֹדֵעַ לְדַבֵּר — אָבִיו מְלַמְּדוֹ תּוֹרָה וּקְרִיאַת שְׁמע

a -We discussed the topic if there is an obligation of teaching a child לשון הקודש.

As Rashi writes דברים יא, יט 

מִכָּאן אָמְרוּ כְּשֶׁהַתִּינוֹק מַתְחִיל לְדַבֵּר אָבִיו מֵשִׂיחַ עִמּוֹ בִּלְשׁוֹן הַקֹּדֶשׁ וּמְלַמְּדוֹ תוֹרָה.

Mentioned the Rambam that explains the Mishna in אבות  , 1 2

וֶהֱוֵי זָהִיר בְּמִצְוָה קַלָּה כְבַחֲמוּרָה,

What is a מצוה קלה? Writes the Rambam…. Learning to speak לשון הקודש!

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אח”כ אמר שצריך ליזהר במצוה שיחשב בה שהיא קלה כשמחת הרגל

ולמידת לשון הקדש

bWe mentioned the חתם סופר   that לשון הקודש will only last as a language if its speakers keep to a level of קדושה. He adds that this is the reason בני ישראל forgot לשון הקודש in the 70 short years they were  בבל. Their lack of קדושה caused them to forget the language.

More on this interesting topic in the future, BL”N.