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 Beshalach


May one open a bag of potato chips on Shabbos, and if the answer is yes, how?


The first part of the question involves the issue of either Binyan b’keilim – Construction of Utensils, or Makeh b’Patish – applying the finishing touch.

According to the halacha one is forbidden to construct an item or utensil, even for temporary use. For example, it is forbidden to construct a paper cup even though it will be discarded after use.In our case we have to understand whether opening a bag of potato chips is called making a k’li or not.


What has opening a bag of potato chips have to do with making a k’li?


The answer is that we find in the gemora [1] that one is prohibited to bore a hole into a barrel in order to extract its contents, because it enhances the barrel. The gemora tells us that fashioning an opening in a k’li is tantamount to manufacturing a k’li.


Then it sounds like the dilemma is solved and opening a bag of chips is forbidden?


Not really, because we find another halacha in the Shulchan Aruch [2] which says that one is permitted to slice open a basket-weave type box in order to retrieve its contents, and we do not see the slicing of the box as making an opening.


When then does the halacha consider the opening as making a k’li and when does it not?


The answer is that since the basket-weave type box was only used for storing its particular contents on a one-time basis and subsequent to opening the box is discarded, it is analogous to a nutshell, which may be cracked and is not called a k’li. A box, which is discarded when its contents are depleted and is not reused, is not called a k’li and may be opened.

Rav Moshe Feinstein, [3] Rav Shlomo Zalman Auerbach and many others presented this concept.

A k’li that is reused for storing items or food is considered a k’li and making any type of opening is forbidden.

Obviously nobody is going to reuse the potato chips packet once it's empty and therefore opening the bag cannot be considered making a k’li. Therefore we conclude that opening such a bag is permitted.


Does that mean that it can be opened in the normal manner?


Rav Shlomo Zalman [4] says that packets can be opened in the normal manner. However some understand from the Chazon Ish, [5] who says that an envelope may only be opened when destructed to the point that it can no longer be used to store anything, that packets etc must be cut or opened in a way that they cannot be reused.

Others say that the an envelope is different, being that it is often reused to store the letter, but packets and boxes which are always discarded upon depletion of its contents are not subject to that edict and may be opened in the normal manner. [6]

To summarize: One may open packets of food [7] on Shabbos. Some say that they may be opened in the normal manner and some say that one must rip the packet and render it unusable.


What about the opening of tin cans?


In today’s affluent society, most tin cans share the same destiny as potato chip packets and are discarded upon depletion. The Chazon Ish [8] commences saying that when one does not intend using the can, opening it is not called making a k’li.

However he adds, “Since many people intend using the tin can for storing soaps, nails etc, there is room to prohibit the opening of the can lest he has in mind to use it”. Many poskim [9] say that the Chazon Ish was only referring to his times when tin cans were often used for storing etc, but nowadays even the Chazon Ish would agree that there is no problem opening a tin can that one does not intend using. Nevertheless, certain poskim say that one should puncture one side of the can and open the other side thus avoiding the problem of making a k’li, because one will surely discard a can with a hole in the bottom.

Rav Shlomo Zalman Auerbach says [10] that one may open a tin can in the normal fashion, being that it is discarded after use. In order to avoid this issue one should open tin cans he intends using before Shabbos.

[1] Shabbos 146a.

[2] Simon 314:8.

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

[4] SS”K 9 footnote 19, SS”K vol. III 35 footnote 63.

[5] ???"? ??' ?? ??"?.

[6] See the Binyan Shabbos page 229, where he thus explains the Chazon Ish.

[7] Packets containing food, clothing, toys, medication etc are all in the same category – Rav Shlomo Zalman Auerbach in the SS”K 3rd vol. Chapter 9 footnote 11.

[8] Chazon Ish simon 51:11.

[9] ???? ???? ?"? ??' ?? ??? ?"?, ???? ???? ??' ???, ??? ????? ?"? ??' ?"?.

[10] See the Binyan Shabbos chapters 33-35.

Food For Thought

What is the halacha with regards to pop-up soda cans?


What can you tell me about opening soda bottles or grape juice bottles?

Answers coming next week.

Vort on the Parsha

The possuk says 'Hashem Yimloch L'olam Va'ed' translated by the Targum as Hashem’s kingdom reigns forever, where seemingly it should have been translated in the future tense – Hashem’s kingdom will reign forever?

The answer is that we say 'Hashem Melech' – Hashem is King, and only then do we say that He was a King and He will be a King. That is because a person cannot declare that Hashem will be his King if he does not accept His reign in the present, it would be an empty declaration.

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.