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Weekly Shabbos Halacha Series
Halachos Series on Hilchos Shabbos

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Published by
Pirchei Shoshanim

A Project of
The Shema Yisrael Torah Network

Written by

Rabbi Dovid
Ostroff, shlita


These Halachos were shown by Rabbi Ostroff to
HaGaon HaRav Moshe Sternbuch, shlita



Questions for the Week of Parshas Re'eh


Tying Knots cont.

If one must tie a knot on Shabbos, either for the sake of a mitzvah or for safety reasons, is one permitted to do so

The Shulchan Aruch says [1] that when necessary, for the sake of a mitzvah, one is permitted to tie a knot that would normally be forbidden midrabanan. [2] This is not a blanket heter because the Magen Avraham [3] says that this is on condition that a normal permitted knot would not suffice.

For example, one may tie a rope to fence a hole in the ground to prevent people from getting hurt. Tying a slipknot or a bow, which are permitted knots, would not suffice as it leaves potential danger; one is permitted to tie a craftsmans knot with the intention of leaving it tied for a short time. Such a knot is normally ossur midrabanan, but to facilitate for a mitzvah Chazal permitted it.

The Pri Megadim raised an interesting question.

Since one is permitted to tie a rabbinically forbidden knot for the sake of mitzvah, why then if ones tzizis tore on Shabbos, or if one does not possess a garment with tzizis is one forbidden to make tzizis on Shabbos? The solution supposedly would be to tie the tzizis intending to untie them after Shabbos, thereby only tying a rabbinically forbidden knot as it is not permanent.

The Biur Halacha [4] explains saying that one does not look at the individuals intention rather at the global manner of tying those particular knots. Since knots tied in tzizis are always permanently tied, it would not help deciding or intending to untie them after Shabbos and they remain a knot that is biblically forbidden to tie on Shabbos. Therefore there is no option on Shabbos but to remain without tzizis that Shabbos.

Am I permitted to untie a double knot that is causing distress?

If one tied the cords on one's robe in a double knot intending not to untie the knot for a few days (being it his habit to slip off the robe without untying the knot). He later realized that the cords are too tight and he cannot slip off the robe. The option other than opening the knot would be to remain inside the robe until the end of Shabbos with all the discomfort entailed. In such circumstances he may untie the knot. [5]


  • The same scenario, but one tied a double knot in ones shoelaces also not intending to untie them for a few days. He later realized that he cannot slip off his shoes. This, of course, prevents one from getting into bed etc, which causes a great deal of annoyance and discomfort. Seeing that the knot is a rabbinically prohibited knot and it causes great distress it may be untied.

How is a slipknot classified?

Although the gemora Shabbos 113a says that there is a dispute between the Chachamim and R Yehuda as to whether a slipknot or a bowknot is considered a knot, the halacha is according to Chachamim who hold that it is not a knot at all.

Accordingly one is permitted to tie a slipknot indefinitely and as tight as one likes because it is not classified as a knot.

How does the halacha classify a bow over a single knot?

Although a bow is not called a knot, as stated above, a single knot with a bow is considered a knot. The best example is the single and bow with which we fasten our shoes. It is not that the bow evolves into a knot because of the single knot beneath it; rather it is because the single knot, which is also not classified as a knot, now stands firm. [6]

Is a bow over a single knot completely permitted without restrictions or are there rules that must comply?

The bow by itself and the single knot by itself do not have rules and regulations and they may be tied forever. The combination of the bow and the single have to comply with the rules of tying knots. Therefore one is forbidden to intentionally tie ones shoes (with a single knot and bow) for longer than 24 hours. [7] One is forbidden to tie a plastic bag with two handles into a single and a bow when he knowingly intends it to remain tied for longer than 24 hours. Therefore challah or bread placed into a bag with the intention of not untying it for the next 24 hours may be tied into a bow without the single knot beneath it.

What if I do not know when I will need the challah or bread?

The Taz [8] and the Shulchan Aruch HaRav say that if one does not intentionally tie for longer than the permitted period, and one often unties it within the permitted time, one may tie it on Shabbos. Therefore when tying the bread bag (with a single and bow), since one may require the bread within 24 hours, even though 24 hours might pass before one opens it, one may tie the bag.

If you habitually tie your shoes without thinking when you will untie them and sometimes you (excuse me) just kick them off, since it is possible that you will untie them within 24 hours it is permitted.

[1] Simon 317:1.

[2] The says that this halacha is only according to the Rif and the Rambam but according to Rashi and Tosefos such a knot is ossur even for the sake of a mitzvah. This is quoted but MB 317:13. The Shulchan Aruch HaRav and other poskim did not mention the . See also the SSK 15:49 in footnote 162.

[3] See MB 317:12.

[4] BH simon 317:1 .

[5] Rama siman 317:1.

[6] " ," ".

[7] MB 317:29.

[8] Taz Simon 317:2 and the Shulchan Aruch HaRav 317:1.


Vort on the Parsha

The possuk says Re'eh see, I am giving you b'rachah and k'lalah, which is unusual because we often find in the Torah the word hear, as in Shema Yisrael, or understand. How is sight applied in this instance?

The S'lonimer Rebbe says that we know that the yetzer tov must counter the Yetzer rah, but it seems unequal, because the yetzer rah seemingly overpowers us with sight we see evil things that have tremendous influence over us and we don't have much to overpower that; surely we should have something to use to balance it out?

He answers that Emunah was given to us from Hashem in such a clear way that it is equivalent to sight. B'nei Yisroel saw the voices at Har Sinai their Emunah was tangible. Here too the Torah says, See you have b'rachah and k'lalah, because our Emunah can be as concrete as a seeable object. With concrete Emunah we can fight the seductions of the Yetzer Harah. You might ask that our level of Emunah is not that strong. The answer is that you can bring it to that level because we were all at Har Sinai and we all have the ability to ascend to that level.


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Note:  The purpose of this series is intended solely for the clarification of the topics discussed and not to render halachic decisions. It is intended to heighten everyone's awareness of important practical questions which do arise on this topic.  One must consult with a proper halachic authority in order to receive p'sak.