shabbos candles

Weekly Shabbos Halacha Series
Halachos Series on Hilchos Shabbos

shabbos candles

Published by
Pirchei Shoshanim

A Project of
The Shema Yisrael Torah Network

Written by

Rabbi Dovid
Ostroff, shlita


These Halachos were shown by Rabbi Ostroff to
HaGaon HaRav Moshe Sternbuch, shlita



Questions for the Week of Shemini


What is the halacha with regards to using a hot water bottle on Shabbos?

            A hot water bottle is used either to warm ones bed in the winter or is placed on the abdomen to ease stomach pain. There does not seem to be any halachic reason why one should not be able to use it to warm ones bed. However, if we transport ourselves to a time when there were no pre-manufactured hot-water bottles and people would use an open vessel and place it on their stomach, we will understand what the Shulchan Aruch is referring to.

The Mechaber says [1] that it is forbidden to place a kli with hot water on ones stomach even during the week. The reason is because the water might be boiling hot and endanger the person. Rashi adds [2] that on Shabbos it is doubly ossur because the water might spill on ones body resulting in a person bathing on Shabbos in hot water. We are referring to water heated on Shabbos and therefore one may not wash even a small portion of ones body with this water. [3]

            Is there a problem using a closed kli?

            We find a machlokes Rishonim. According to Rashi who holds that the problem is that we are concerned lest the water spills on ones body, when the kli is closed, like contemporary hot water bottles, there is no problem. According to Tosefos who holds that one may not place a kli with hot water on ones abdomen because it is considered using medication, even a closed bottle is prohibited. Accordingly, when ones intention is merely to warm ones bed, one may use a closed water bottle.

            Does that mean that it is forbidden to ease a stomach ache with a hot water bottle?

            If a person is classified as ill, which means that he is either bedridden, [4] or his entire body aches, [5] he may use a hot water bottle. If one is not classified as ill, one may not use any medication, and since placing a HWB on ones stomach is a type of medication one may not use it. However, in the winter months, where it is common that one places a HWB in ones bed for warmth, one may do the same when one has a stomach ache. This is based on a rule which says that one may administer medication when it is something that healthy people do as well. [6] For example, healthy people drink brandy, therefore one who has a sore throat or a toothache may drink brandy in the normal manner, even though ones intention is to ease the sore throat. One may not gargle with the brandy because then it becomes noticeable that ones intention is for medicinal purposes.

Hence, in the winter months one may place a HWB in ones bed even when ones intention is medicinal because healthy people do so as well. [7]

One may nevertheless heat a towel and place it on ones stomach, as that is not something associated with medicine. [8]

            Is one permitted to immerse oneself in a mikveh on Shabbos?

            The Mechaber says that one may immerse in a mikveh on Shabbos. This heter dispels two problems. The main problem is that although we rule that it is forbidden to immerse a tameh vessel in a mikveh on Shabbos, [9] nevertheless a person may immerse himself in a mikveh. [10] The second problem is that although our custom is not to bathe even in cold water on Shabbos, immersion is permitted.

According to many poskim, men [11] who immerse on Shabbos morning should try and avoid the hot water mikveh. This is because bathing in hot water is a rabbinical prohibition, and although we find poskim [12] who permitted it and made a distinction between bathing and immersing, yet we see that the Mishna Berura Siman 326:7 says that the mikveh should only be lukewarm (and colder) but not hot. [13]

            May one make use of a sauna on Shabbos?

            Subsequent to the gzeira prohibiting hot bathing on Shabbos, Chazal prohibited the use of a sauna on Shabbos. This was because people would still bathe after the institution of the gzeira and when caught red-handed they would say that they were merely using the sauna.

            What about the use of a sauna after Shabbos which was heated during Shabbos?

            This question was more pertinent in earlier times, when heating a sauna or bathhouse meant adding wood or coals to a fire and stoking it. We will nevertheless discuss it because this halacha has many ramifications to our current lives.

For the sauna to be hot straight after Shabbos, the bathhouse attendant would have to heat the sauna or baths on Shabbos. Since Chazal prohibited deriving benefit from actions performed by gentiles on Shabbos when performed for Jews, it is imperative to determine whether indeed it was done for Jews.

The Shulchan Aruch [14] teaches us that when the majority of the bathers are gentiles, we regard the heating as being done solely for them and Jews may bathe or sweat in the sauna straight after Shabbos. If the majority are Jews, or Jews and gentiles equally, we regard the heating as being done for the Jews and they may not bathe straight after Shabbos. In such a case they must wait the time of bichdei sheyaasu, i.e. the time it takes to do the prohibited melacha. In this case, if for example it takes 3 hours to heat the sauna or bathhouse, a Jew must wait 3 hours before entering.

            Where is this applicable today?

This applies to any action a gentile performs on Shabbos and is used by Jews after Shabbos. If it takes 2 hours to open and heat up a swimming pool that is used mainly by Jews (separate swimming), and the caretaker makes the preparations on Shabbos, the bathers must wait 2 hours after Shabbos before swimming.

[1] Siman 326:6.

[2] See MB 326:19.

[3] Shaar Hatsiun 326:9.

[4] Or at least in a situation where one should go to bed.

[5] Siman 328:17.

[6] Siman 328:37.

[7] See the SSK 34:11.

[8] MB 326:20.

[9] MB 323:33.

[10] The reason is because often a person would rinse oneself in cold water on Shabbos (before it was accepted not to bathe) and when one bathed for mikveh purposes it was not noticeable.

See the MB 326:24.

[11] It is customary for the other gender to immerse in hot water as well, see the SSK14 footnote 4.

[12] " ' '.

[13] The Tchebiner Rov ztzl went to immerse in a mikveh Shabbos morning, and after putting his foot in the water he exclaimed its heis (hot) and got dressed and left without immersing.

[14] Simon 326:13.



Orchos Chaim LaRosh

keep a distance from ridicule.

Laughter is healthy but making fun of people is not. removes fear of heaven and also prevents ever being rebuked. teaches us that one mock can refute one thousand rebukes, because instead of dealing with the rebuke and appreciating its truth, one can mask it with and hide behind its insincerity.

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.