shabbos candles

The Shabbos Weekly
Halachos Series on Hilchos Shabbos

shabbos candles

Published by
Pirchei Shoshanim

A Project of
The Shema Yisrael Torah Network

Based on the Shiurim Given by

Rabbi Dovid
Ostroff, shlita

developed from the Chabura of the
Pirchei Shoshanim Shulchan Aruch Learning Project

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


Questions for the Week of Parshas Vayechi


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

In the previous sheet we classified a tight double knot as a craftsman’s knot and as such it is prohibited to knot on Shabbos even for a short while. However, the nature of such a knot when coupled with a short time span is only a rabbinical prohibition [1] and Chazal permitted its untying when it causes distress. [2]

  • If one tied the cords on his 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 his robe until the end of Shabbos with all the discomfort it entails. In such circumstances he may untie the knot.
  • The same scenario but one tied a double knot in one’s 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 stress 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 the Chachamim who hold that it is not a knot at all.

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

How do you 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. [3]

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

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 does have to comply with the rules of tying knots. Therefore one is forbidden to intentionally tie one’s shoes (with a single knot and bow) for longer than 24 hours. [4] 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 [5] and quoted by the Shulchan Aruch HaRav say that if one does not intentionally tie for longer than the permitted period, and he often unties it within the permitted time, he 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 he opens it, he 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.

Is there any particular way a Sefer Torah must or must not be tied?

The optimal fasteners for a Sefer Torah are either a belt with a clasp or the Jewish German custom – the wimple. Using a belt fastened with a knot and a bow presents a problem because if that Sefer Torah will not be used until Monday or even worse, until the following Shabbos, in effect he is tying a knot for longer than 24 hours and sometimes for longer than 7 days.

Those that do have such a belt or cord have what to rely on because there are opinions which hold that one may tie a knot for the sake of a mitzvah, which in our case is fastening the Sefer Torah. [6] Nevertheless the optimal preference is one of two fasteners mentioned above.

[1] A biblical prohibition (according to the Rif and the Rambam) requires the presence of both craftsmanship and permanence.

[2] Simon 317:1 in the Rama.

[3] ???? ??? ??"? ??,??"? ??"?.

[4] M”B 317:29.

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

[6] Mechaber 317:1 and M”B 12. In M”B 13 he quotes the ??? ???? who learns that according to Rashi and the Rosh there is no such heter. See the SS”K 15 footnote 178.

Food For Thought

Am I permitted to insert a new shoelace into a shoe on Shabbos?

Am I permitted to swap shoelaces, i.e. to transfer shoelace from shoe A and place it in shoe B?

If the cord in my pajama trousers came out am I permitted to restring it on Shabbos?

Answers coming next week.

Vort on the Parsha

Ya’akov Avinu blessed Yosef saying that when one will want to bless his children he will say “Yesimcha Elokim K'Ephraim UK'Menashe”. Rav Ezriel Auerbach shlita explained that the uniqueness of Yosef was that from within the lowest point in his life – the prison pits of Egypt – from where nobody goes anywhere and all is totally lost, he rose to the pinnacle of success and power. This teaches us never to despair and give up hope. In our extremely dark and horrendous gollus we must bless our children with the remembrance that from the most hidden depths one can rise to unimaginable heights. B”H we will all soon see the true geulah.

For a printed version, click here.


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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.