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 Yisro


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


The Mishna Shabbos 146a teaches us that one is permitted to break open a barrel on Shabbos to retrieve its contents provided that he does not create a ‘nice’ opening. The Ran explains that making a nice opening converts the barrel into a k’li. In other words, it is not the physical nicety, which is forbidden rather it is the objective achieved by creating a nice opening.

Accordingly, one would be permitted to fashion a ‘nice’ opening if the vessel would not be deemed a k’li.

We brought opinions in the previous sheet who learn that one may open packets, tin cans etc and it is not called ‘fashioning a k’li’ because the container is discarded upon depletion. Even though the opening of a tin can is a ‘nice’ opening, nevertheless since the can is not reused, it is not called a k’li and may be opened regularly (according to the lenient opinion).

We can apply the same logic to a pop-up soda can. Even though the opening fashioned when pulling the tab is a ‘nice’ one, since the can is not reused upon depletion, it is not called making a k’li and may be opened normally on Shabbos. [1]

Others may disagree and say that, after all, one is fashioning a nice opening and one may not open it in the normal manner on Shabbos.

According to the stringent opinion who prohibits opening such a can on Shabbos, a solution would be to pry open the tab just enough to allow the insertion of a straw but not enough to enable practical use of the can.

What’s with the boxes of fresh juice that have a small hole covered with aluminum foil?

The Mechaber says that a sealed opening above the dregs is not a proper seal and may be reopened on Shabbos. [2]

Hence, everyone agrees that the foil or paper may be pierced on Shabbos because the opening is already there and one is merely removing its covering.

Is one permitted to remove the paper or aluminum foil covering off a coffee jar?

The Bais Yosef [3] quotes a Tosefta that says the following:

One may slash the leather covering the mouth of a barrel providing he does not intend to form a spout.

A coffee jar is sealed with a piece of paper or aluminum foil, which is torn off before the initial use. The Tosefta seems to be referring to a case very similar to ours and one is therefore permitted to tear off the paper sealing the jar.

The Tosefta stipulates that one not form a spout with the leather atop the barrel. This means [4] that one may rip the leather haphazardly taking care not to form a spout with the torn pieces. When entirely removing the piece of paper stuck to the coffee jar or when removing the aluminum foil one is not forming a spout, rather one is merely exposing the opening of the jar. Rav Sternbuch shlita points out that tearing the paper in a way that it can still be used is forbidden.

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


The problem with opening soda bottles or grape juice bottles is the removal of the ring attached to the top thereby creating a k’li – the top. We must differentiate between the metal caps and the plastic ones because they are manufactured differently and hence carry different halachik ramifications. Here too the poskim disagree as to whether it is permitted or not.

Metal Caps – we are referring to the metal caps sealing a grape juice or wine bottle, where the attached ring is also metal. Here there is almost a consensus [5] to prohibit the opening. The cap as it is on the bottle cannot be used to close other bottles (if hypothetically you would remove the cap without detaching the ring) and only upon detaching or widening the ring can it be used. By detaching it you are making it into a k’li.

The solution would be to puncture the cap with a knife etc and then open it thereby revoking its use as a k’li, being that such a cap is not used for other bottles and is discarded.

Plastic caps or rings – Many authorities attribute the same features with these caps as with the metal ones and forbid opening them on Shabbos. Others distinguish between the two. The lenient opinion holds that since the plastic cap is screwed on in the factory with the ring attached, unlike the metal one which is shaped on the bottle and cannot be screwed on with the ring attached, in effect it is already a k’li before the ring is detached and detaching the ring does not create a k’li. Accordingly one is permitted to open such a cap in the regular manner. [6]

[1] This opinion is shared by Rav Shlomo Zalman Auerbach as quoted in the Binyan Shabbos page 208.

[2] Simon 314:3.

[3] In the beginning of simon 314.

[4] Binyan Shabbos page 221.

[5] There are poskim who permit it saying that one does not intend making a k’li.

[6] Rav Shlomo Zalman Auerbach as brought down in the Binyan Shabbos and in the Me’or HaShabbos.

Food For Thought

Can you please define the essence of the melacha called Borer?

What are the cardinal rules of Borer?

 What happens if I removed an item I thought I wanted and then either changed my mind or realized I did not want it, must I then use or eat it?

If I mistakenly separated food contrary to the halacha am I permitted to eat it?

Answers coming next week.

Vort on the Parsha

Rashi in the beginning of the parsha says that a portion of the Torah was attributed specifically to Yisro. What was the reason for naming a parsha after Yisro? Just because he advised Moshe Rabeinu to set up batei dinim (courthouses) he merits such honor?

The Alter Gerrer Rebbe said that it is easy to rebuke and criticize but much harder to be constructive.

Yisro criticized Moshe saying that one cannot judge an entire nation single-handedly, but he did not end there. He then came up with an incredible plan-of-action, which was later blessed by Hashem and implemented.

Offering sound advice merits a reward.

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.