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 Chayei Sarahsubscribe


I heard that when setting up a ping-pong table on Shabbos one must reverse the order, i.e. first hold the board in the air and then position the legs, is this true? 

No, it is false and the following will explain why.
The Gemora in Beitza 32b teaches us that certain keilim when erected on Shabbos must be erected in a backhanded manner, i.e. different to the way it is normally set up. This is because when erecting these particular keilim it appears as if one is making a tent – first the legs and then the roof or cover – and therefore a variation from the norm is required.
However, this only applies to keilim whose function is similar to a tent’s. Just as a tent’s inside is utilized for living in, usage etc, so to keilim whose ‘inside’ or ‘underside’ is used require a deviation when setting up.
A table, Tosefos
1 tell us, is not an item whose underside is used and therefore it would not require deviation from the norm and may be set up in the regular manner.
Therefore when setting up a ping pong table one may first position the legs and then place the board on top of the legs.

Do you have an example of a k’li where the deviation from the norm is necessary? 

The gemora tells us that one uses the space beneath a bed and the Rishonim say that it is used for storing shoes or sandals during the night. (Food is not stored beneath a bed because an unclean ruach descends upon the food). However, Tosefos says that although the underside is used, since it is not the primary reason for setting up the bed, one need not change from the norm unless the bed has two sides (headrest and footrest for example) that either reach the floor or are within three tefachim 2 from the floor.

In such a case one must first hold the board in the air and then slide the legs in underneath. Since it is setup in an awkward manner one will remember that tent erecting on Shabbos is forbidden and will not erect a tent.

What about setting up a bench on Shabbos? 

It has the same halacha as a table, because a bench’s underside is not used either.

What is the halacha regarding the use of barrels as table legs when the barrel is being covered by the board?

This issue is based on the previous one. The Taz says that covering a four-sided k’li automatically accredits it as a usable space and requires a deviation from the norm. Since a barrel has four sides, when using it as table legs one must hold the board in place and then slide in the barrel.

The Shulchan Aruch HaRav 3 disagrees with the Taz and permits erecting a table even when it has four sides but the Mishna Berura 4 paskens like the Taz.

Does it make a difference whether the legs were already in position?

A crucial point. The Mishna Berura 5 says that one is only required to vary from the norm when one first positions the legs and then places the top but if the legs were already in position and one is merely placing the top, no deviation is necessary.

This is because Chazal required a deviation from tent building, which is usually accomplished by positioning the sides and placing the roof. In this case it does not resemble tent building and hence no need for the deviation.

Is there a problem covering a wide bath or tub on Shabbos?

In yeshiva there used to be a large, wide tub on wheels which was used for storing the bread and challa used for Shabbos. The Shulchan Aruch 6 says that when covering a large tub one must make sure that he does not completely cover the tub. Another way around the problem is if the contents of the tub reach the top, because an ohel is fashioned when there a space of at least a tefach3 (squared) is covered, but when the contents reach the top an ohel is not formed, thereby sidestepping the entire issue.

[1] Tosefos in Beitza 32b ‘milmata.
[2] Either 24cm or 28.8cm.
[3] Hilchos Yom Tov simon 502:6.
[4] Simon 315:22.
[5] Ibid. See also the Chazon Ish 52:1-2.
[6] Simon 315:13.

Food For Thought

If a bird flies into the house through an open window, am I permitted to shut the window?

Does the same halacha apply to flies and insects?

What about a bread box with flies or bees flying inside, am I permitted to shut it?

If a bee (the honey maker) is disturbing me in my succah am I permitted to trap it?

Answers coming next week.

Vort on the Parsha

We see that Avraham Avinu first eulogized Sarah and only then did he involve himself with the buying of a burial site. Should it not have been the opposite?

Rav Sternbuch shlita duly explains that certain measures of persuasion were required for the acquirement of the cave and the surrounding field. Avraham Avinu therefore had to first demonstrate Sarah’s greatness hoping that B’nei Ches would accede to his proposition.

The Torah does not portray Avraham’s eulogy, however Rashi says that Sarah’s 127 years were all ‘good’. That was the hesped! Sarah Imeinu remained steadfast in her service of Hashem regardless of time, place and age. No matter what personal trials and tribulations she was going through, she stood fast.

A woman of such valor and stature surely deserves the cave of Machpela.

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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.