Question:
This year the weather is extremely hot. The second night of Rosh Hashanah falls on Motzei Shabbos, and I have a long walk to and from Shul. By the time I return home, I will be sweaty and uncomfortable, and I find it very difficult to fall asleep in such a condition. May I take a shower before going to sleep on the second night of Rosh Hashanah? May I use warm water? May I use soap and shampoo?
Short Answer:
In a case of genuine discomfort due to heat, perspiration, or difficulty sleeping, one may shower on Yom Tov using cold water. Furthermore, one may even use lukewarm water that does not have a noticeable hot sensation. The main issue is not the act of showering, but rather how the water is heated.
Accordingly, if opening the hot-water faucet will activate a gas flame or electric heating element, then one is not to do so. However, if there is already hot water available from before Yom Tov and opening the faucet will not activate any heating system, then on Yom Tov one may mix cold and hot water together to achieve lukewarm water and shower with it when needed.
One may likewise use liquid soap. Preferably, the soap should already be in liquid form from before Yom Tov. Regarding washing one’s hair with liquid soap or shampoo, from the letter of the law it is permitted so long as one is careful not to squeeze the hair in the process. Nevertheless, the accepted custom is to avoid washing the hair of the head with soap or shampoo on Shabbos and Yom Tov.
One must also be careful not to squeeze water from one’s hair during the shower.
Explanation
One of the areas of Yom Tov observance that often creates confusion is the subject of bathing and showering. Some people assume that a shower on Yom Tov is no different than a shower during the week and is therefore automatically permitted. Others assume that all showering on Yom Tov is forbidden. In truth, the halacha is considerably more nuanced.
To properly understand the issue, we must first distinguish between three different types of water:
- Hot water
- Warm or lukewarm water
- Cold water
Each category carries its own halachic considerations.
The General Restriction Against Hot Showers on Yom Tov
Although Yom Tov permits certain melachos for food preparation and bodily enjoyment, Chazal nevertheless prohibited bathing one’s entire body with hot water that was heated on Yom Tov. Furthermore, the accepted Ashkenazi custom is to be stringent even regarding a full-body hot shower using water that was heated before Yom Tov. Accordingly, one may not simply decide to take a standard hot shower on Yom Tov in the same manner that he would during the week.
Cold Showers Were Never Included in the Original Decree
However, the decree of Chazal was directed primarily toward hot water. From the letter of the law, bathing in cold water was never prohibited even on Shabbos. Although an Ashkenazi custom developed to generally avoid bathing even in cold water due to various concerns, the Poskim explain that this custom was never intended to apply in situations of significant discomfort. Thus, if a person is sweating heavily, suffering due to the heat, unable to relax, or finds it difficult to sleep because of physical discomfort, the Poskim permit showering in cold water. This is especially relevant on Rosh Hashanah in hot climates, where a long walk to and from Shul can leave a person feeling exhausted, overheated, and uncomfortable.
What About Lukewarm Water?
Many people are able to tolerate a cold shower during the daytime but find it difficult late at night. This raises the question: Must the shower be completely cold?
The answer is no.
The Poskim explain that whenever a cold shower is permitted, one may likewise use water that is merely lukewarm. Lukewarm water refers to water that is below body temperature and whose warmth is not significantly felt. It is not considered “hot water” for purposes of the bathing prohibition. Therefore, if one is uncomfortable taking a completely cold shower, he may use mildly warm water in a time of need.
The Real Question: How Was the Water Heated?
At this point, we arrive at the main practical issue.
The primary question is not whether one may stand under lukewarm water. Rather, the question is how that water is being produced. If opening the hot-water faucet causes an electric heating element or gas burner to activate, then opening the faucet will involve prohibited Yom Tov activity and may not be done. However, many homes have hot water already available in the system from before Yom Tov or from permitted sources. In such a case, if opening the faucet does not trigger any new ignition or heating process, then one may use that existing hot water.
Practically, one may open the cold water faucet and then add some already-available hot water in order to create lukewarm water suitable for showering. Since no new fire is being created and no prohibited heating is occurring, this is permitted in a case of need.
Solar Boilers and Leftover Hot Water
In many places, hot water remains available from a solar boiler or from water heated before Yom Tov. Practically, one must ensure that drawing the water does not activate any backup electric or gas heating mechanism. If no heating system is activated, then one may use the already-heated water for the permitted purposes described above.
May One Use Soap and Shampoo?
Another practical question concerns soap and shampoo.
Liquid soap may be used while bathing or showering on Yom Tov. Preferably, it should already be in liquid form before Yom Tov.
Regarding washing the hair, from the letter of the law many Poskim rule that one may use liquid soap or liquid shampoo even on the hair, provided that one is careful not to squeeze the hair during the washing process. Nonetheless, the practical custom is to refrain from washing the hair with soap or shampoo on Shabbos and Yom Tov. Accordingly, while there is halachic basis for leniency, one should follow the accepted custom unless there is a particular need. In all cases, one must be careful not to squeeze water from the hair, beard, or peyos.
Is This the Preferred Practice?
Although the above leniencies exist, it is important to note that the traditional custom amongst Ashkenazim was generally to avoid bathing on Yom Tov unless there was a genuine need.
Nevertheless, the Poskim explicitly state that where a person is suffering due to heat, perspiration, discomfort, or similar concerns, he is not required to maintain this stringency.
Accordingly, in the question presented, where the individual has a lengthy walk, is heavily perspiring, and expects difficulty sleeping due to discomfort, there is room to permit a shower using cold or lukewarm water obtained in a halachically permissible manner.
Summary Table
| Situation | Ruling |
| Cold shower due to heat and perspiration | Permitted |
| Lukewarm shower below body temperature | Permitted in a case of need |
| Regular hot shower | Forbidden |
| Opening hot water that activates a burner or heating element | Forbidden |
| Mixing existing hot water with cold water to create lukewarm water | Permitted if no heating system activates |
| Using liquid soap | Permitted |
| Using liquid shampoo | Permitted |
| Squeezing water from hair | Forbidden |
Sources:
- Regarding the prohibition of bathing with hot water on Yom Tov: Admur 511:1; Michaber 511:1-2; Rambam Hilchos Yom Tov 1:16.
- Regarding the permissibility of cold-water bathing and the Ashkenazi custom: Admur 326:1, 6; Michaber 326:1; Bach; Maharil 139; Terumos Hadeshen 255; Beis Yosef Y.D. 199; M”B 326:21
- Regarding showering due to heat, perspiration, and discomfort: Ketzos Hashulchan 133 footnote 8 [towards end]; Igros Moshe 4:74; Beir Moshe 6:73; Dvar Yehoshua 2:54; Az Nidbaru 1:61; SSH”K 14:1; Piskeiy Teshuvos 326:8; Shabbos Kehalacha 18:40; Minchas Yitzchak 6:32
- Regarding the permissibility of lukewarm water: Supplement from Mahadurah Basra chapter 259 Page 884 in the new Shulchan Aruch regarding water heated before Shabbos, and the same would apply here to water heated on Yom Tov, which has the same status as before Shabbos; Chacham Tzevi 11 who forbids for women to immerse in water on Shabbos that is called hot, rather it must be cold or slightly warm; Nodah Beyehudah Tenyana Orach Chayim 24 that women may bathe in warm Mikvaos but not hot Mikvaos; Aruch Hashulchan 326:3; P”M 511 M”Z 5; Ashel Avraham Buchach 326; Tehilah Ledavid 326:3; Minchas Shabbos, brought in Ketzos Hashulchan 133 footnote 1; Shevisas Hashabbos Mevasheil 125; M”B 326:7; Igros Moshe 1:126; SS”K chapter 14 footnote 3; Piskeiy Teshuvos ibid; Shabbbos Kehalacha ibid;
Other Poskim: Some Poskim rule that it is forbidden to bathe in warm water just like hot water [Beis Meir Y.D. 197:3; Rambam brought in Biur Halacha; However the M”B himself 326:7 writes that bathing in warm water is allowed [for Mikveh]. Some however write that in truth the M”B holds that only water in which some coldness is felt is allowed, and it is by this warmth that he allows to bathe, however water which its heat is felt is forbidden as writes the Rambam, as he brings in Biur Halacha. [Az Nidbaru, brought in Piskeiy Teshuvos 326:2].
- Regarding opening the hot-water faucet when it does not activate heating: Piskei Teshuvos 511:7.
- Regarding water heated by a solar boiler and similar systems: See discussion in Piskei Teshuvos 326:2; 511:5.
- Regarding liquid soap and bathing precautions, including not squeezing hair: Admur 326:6; Sheivet Halevi 5:45; Shemiras Shabbos Kehilchasa chapter 14; Piskeiy Teshuvos 326:11