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 Ki Seitzeisubscribe


There is a famous statement, which says ‘ein binyan b’keilim’ – there is no prohibition with regards to the construction of items. Does this hold true?

Although the gemora in Beitza 10a says that ‘ein binyan b’keilim’ – there is no prohibition with regards to the construction of items, the Rishonim explained that this statement is referring to some very specific cases. For example, Tosefos 1says that assembling the various parts of a k’li are permitted unless force and craftsmanship are required. (One cannot deduce from this that every assembly of keilim, unless force is used, should be permitted, because there are many restrictions, as we will B”H see). In such a case the assembly would be a Torah transgression of Building A K’li.

The Ramban, in the beginning of the 12th perek of Shabbos says that ein binyan b’keilim refers to the assembly of keilim that have come apart, but making a k’li from scratch is definitely Boneh. 2He adds, that according to this opinion, if a k’li came apart in such a way that it requires a craftsman to reassemble it, the assemblage would be classified as Boneh, because subsequent to its detachment it lost its status as a k’li, and its assembly is the making of a k’li. The Maggid Mishne explains the Rambam (10:13) in this fashion as well.

Is one permitted to erect a baby’s crib on Shabbos?

We first have to realize that the poskim regard the tightening of nuts and screws as a full-blown prohibition.3 Therefore the answer would be that it depends on the type of crib it is. If it is a folding crib and its assembly does not require any screwing or forcefully attaching pieces together, it is permitted. If, however, the pieces are screwed or fastened tightly to each other, it is forbidden to assemble the crib. 4

In addition, it is forbidden to raise or lower the base of the crib, if this is accomplished by firmly inserting a rod into a hole in the frame. If however, the rod is made to slip easily into the hole in the frame it would be permitted.

If screwing pieces together is forbidden, how is it that we screw shut a baby’s bottle?

There is a vast difference between the crib and a baby’s bottle. A baby’s bottle is continually opened and closed as part of its use, whereas the crib does not need to be dismantled as part of its use.

The gemora says 5that if one were to assemble on Shabbos a traveling salesman’s bed he would be liable to bring a korban, i.e. he would have transgressed a biblical prohibition. The explanation being that although the bed is not assembled for permanency, but since it does need to be dismantled as part of its use, it is deemed as making and completing the k’li. Whereas a baby’s bottle cannot be seen as complete when the top is screwed on and ‘broken’ when it is not, because it is made to open and close continually.

The same would apply to a saltshaker (salt cellar, in English) and to lids that are screwed on. 6

The screw at the base of a thermos flask became loose, am I permitted to tighten it on Shabbos?

A thermos flask is made in such a way that the inner, insulated bottle is inserted within an outer shell and screwed into place. This bottle is not intended to be unscrewed and therefore if it came loose, tightening it would be forbidden.

Conversely the screw on the top of the flask, even though it is shut tightly so as not let the hot water escape, since a sealed flask is useless, its shutting cannot be called ‘making a k’li’ and therefore it is permitted.7

[1] Shabbos 102b ‘hai man’.
[2] The Ramban differentiates between binyan b’keilim – adding or assembling an existing k’li, and Osseh – making a k’li, where the latter is Boneh.
[3] The Sha’ar Ha’tsiun in simon 313:32 says that according to the M”A it is tantamount to an issur d’oraisso and according to the Taz it is an issur d’rabanan. They would both agree that screwing a screw into wood would entail an issur d’oraisso.
[4] SS”K 24:23.
[5] Shabbos 47a.
[6] M”B simon 313:45, Rav Shlomo Zalman Auerbach in the Minchas Shlomo page 70.
[7] The words of the Chazon Ish in simon 50:10 ‘v’ha d’kasvu’.

Food For Thought

Am I allowed to raise and lower a shtender on Shabbos?

What about raising and lowering a fan head, which involves opening and tightening a screw?

The eyepiece of my glasses came out of the frame, am I permitted to return it on Shabbos?

A kiddush cup contraption, which is assembled with screws and is frequently assembled and dismantled, may it be done on Shabbos?

Answers coming next week.

Vort on the Parsha

The Parsha commences with the permission granted to soldiers in war to take home a woman of the conquered nation. The gemora says that the Torah permitted it because Hashem understands the nature of human beings, and appreciates that men cannot withstand such a devastating assault of the yetser hara.

We must not forget that in the previous parsha we saw that only people who were complete and strong in their faith and observance of the mitzvos were allowed to go into battle, and yet here we see that these very people were granted permission not to have to fight the yetser hara. The soldiers in battle, who are engaged in fighting the enemy, are not within their usual self-control, and therefore there is a possibility that they might succumb to the yetser hara. In such a situation Hashem did not demand of them something above their power.

The message to us all is that the Torah does not demand of us to do more than we can, and therefore if we are tempted to sin, it must be that we could persevere if we wanted to.

In the month of Elul, where Hashem offers special assistance, we must reinforce this idea and do our utmost to triumph over the yetser hara.

For a printed version, click here.

Dedicated in memory of Rav Yosef Chaim of Baghdad, author of the ben Ish Chai. 13th of Elul.

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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.