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 Shemos


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

One could easily think that there is nothing wrong in inserting a shoelace into a shoe, being that it does not involve craftsmanship or cutting or any other melacha. Nevertheless Chazal tell us that it involves ???? ???  – making a k’li.

We find the gemora Shabbos 48a saying that one is permitted to reinsert feathers into a pillow they were previously in but not to introduce them into a pillow for the first time. The reason behind this is because the bond between the feathers and the pillowcase form a k’li. The same applies to the shoe:

The shoelace complements the shoe and makes it functional therefore the threading of the lace into the shoe is ???? ???. [1]

Does this only apply to new shoes and new laces?

This halacha applies equally to old shoes, new ones, old laces and new ones. In other words one may not replace a torn shoelace with a new lace or with an old one, regardless of whether the shoe is a new one or an old one. The logic of ???? ??? equally applies because with all these cases a lace and a shoe form a k’li.

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

No, you may not, for the same reason. Even though both shoes are functional, by introducing lace A into shoe B you are again making a k’li. If a shoelace came out you may rethread it into the same shoe because the shoe and the lace have already formed the k’li.

Is this halacha applicable in other areas as well?

Inflating a soccer ball for the first time invokes the same prohibition. This is because a soccer ball is blown up once and introducing air into the ball forms a k’li. This is only true of items that are inflated and are not deflated subsequent to use. A rubber duck, for example, is not subject to this prohibition because it is inflated prior to use and deflated after use. This last halacha is based on the Magen Avraham (317:7) who says that one may thread a belt into trousers on Shabbos because the belt is removed after wearing.

Accordingly it is permitted to thread a ‘wrong’ color shoelace (for lack of a more suitable one) for the first time on Shabbos because it will be removed after wearing. [2]

Likewise if the shoelace would be thread in such a way that one would not leave it as it is, it is permitted.

The idea behind this is that when the two items are permanently united we say that a k’li has been formed but when they are not permanent, we say that one item is merely aiding the other and the two together do not form a k’li. [3]

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

According to the Mechaber one may restring a shoelace, a sandal strap and a hood lace provided that he does not tie a knot in the string. [4] He bases his ruling on the Rambam.

The Mishna Berura [5] and many other poskim base themselves on the Tosefos and the Rosh who hold that one may rethread when two conditions are complied with:

1)        The thread is easy to thread.

2) One does not usually tie a knot subsequent to such a threading.

Accordingly each threading or stringing must be judged individually.

Lacing the hood is rather arduous and would therefore be forbidden to lace on Shabbos. The same can be said of the pajama trousers. Accordingly, even though one is merely restringing the item and as such ‘making a k’li’ would not apply, since it is difficult to restring it, it is forbidden to do so. [6]

Likewise if subsequent to stringing one usually ties a knot to prevent it from slipping out, it is forbidden to insert the string or lace.

[1] M”B simon 317:18.

[2] SS”K 15:60.

[3] See the sefer Binyan Shabbos pages 158-159.

[4] Shulchan Aruch simon 317:2.

[5] M”B 317:20

[6] The Shulchan Aruch HaRav explains that when something is hard to restring it is similar to Makeh B’patish – stringing it for the first time.

Food For Thought

Is one permitted to remove the paper stuck to a Band-Aid on Shabbos?

What is the halacha with regards to opening and sticking a baby’s diaper?

Does Velcro have a status of ‘sticking’ or not?

After I am finished with the diaper, am I permitted to stick the tabs to the diaper to seal it?

Answers coming next week.

Vort on the Parsha

The possuk tells us that Yocheved and Miriam did not do as ordered by Par’oh, the king of Egypt, and they gave life to the children. The question is obvious, if they did not do as Par’oh told them to do, which was to kill all male babies, then obviously the children lived, so why does the possuk seemingly repeat itself?

A possible answer is that remaining passive in the face of evil, endangers one’s self constraints and might slowly drag him into the evil net as well.

Yocheved and Miriam went to the opposite extreme in order to oppose Paroh’s decree and not only did they not kill male babies, they fed and cared for them. Yocheved is identified by the Torah as Shifra, stemming from the word ????  – to improve, and Miriam is identified as Pu’ah, stemming from ???  – to cry. Both Shifra and Pu’ah did their utmost to care and pamper each and every baby in order to radically counter Paroh’s decree.

We see that it is not sufficient to merely stay away from evil; one must oppose it by acting in the opposite direction.

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.