1. The Laws of Bathing on Shabbat, 13 Seifim: One is forbidden to wash his entire body, even when washing one limb at a time, even when using water that was heated before Shabbos, whether the water is in a vessel or in the ground. Even pouring water over oneself and washing is forbidden. Nevertheless one may wash his face hands and feet RAMA: or other limbs as long as he does not wash his entire body. [Beis Yosef in the name of the Rosh] The above pertains to water heated by fire but one may wash his entire body with Tiberius hot spring water and needless to say that he may wash in cold water. One may only wash in Tiberius hot spring water that is in the ground but not in a vessel so as not to confuse it with regular hot water.
2. There are those who say that this is permissible specifically in the hot springs of Tiberius unless the place [where the water is located] has no roof. But if the place has a roof it is forbidden because [the person] will sweat, and it is forbidden to [cause oneself] to sweat on Shabbos. And there are those who say that it is permitted to sweat in the hot springs of Tiberius.
3. When there is a water channel in which water from a natural hot spring flows it is forbidden to run a duct of cold water through it, even from Friday, i.e., the source of the duct’s water is located outside the water channel and its water flows into a [nearby] cavity in the ground, [creating a pool in which to bathe]. (The intent is to warm the water in the duct as it passes through the hot spring’s water). And if one does run (such a duct) it is forbidden, even to use the water that enters it from Friday. If [water] was directed to flow through the duct on the eve of a festival, it is governed by the laws that apply to water that was heated on a festival, i.e., it is forbidden to bathe one’s entire body or the majority of it in [such water]; it is forbidden to rinse one's body in it but it is permitted to drink.
4. One must not pour cold water over one’s entire body and stand next to the fire because he is heating the water on his body and the end result is that it is as if he is washing his entire body with hot water on Shabbos. Nevertheless one may pour cold water over one’s body after warming oneself by the fire.
5. There are those who say that one must take care not to warm one’s hands next to a fire subsequent to washing them unless they were dried beforehand.
6. One is prohibited from placing a flask filled with hot water on one’s stomach, and it is prohibited even on a weekday being it is dangerous, as sometimes the water is scalding hot. [However, one may warm a garment and place it on one’s stomach] [Tur].
7. A person who bathes in a river must dry his body thoroughly when he ascends from the river, so that no water will remain on his body, [and] he does not carry [this water] four cubits in a karmelis, considering that one who ascends from the rinsing has a majority of water on his body. But if he walks in the public domain and there is delightful rain on his head and his clothes, we are not strict with him on this.
8. One is permitted to bathe in a Mikvah on Shabbos in order to get rid of one’s impurity.
9. It is permissible to rinse one's face, hands and legs with substances that do not remove hair that are mixed with substances that do remove hair provided the majority [of the compound] is not composed of substances that will certainly remove hair.
10. It is permitted to rinse one’s hands together with bran. RAMA: because this is considered as kneading [dough] in an irregular manner. It is forbidden to rinse one's hands with salt [Agudah] and certainly not with soap called זיי"ף in Arabic [Binyamin Ze'ev] or other products made from [animal] fat because these [substances] will dissolve in the process, thus bringing a new entity into existence on Shabbos. [Chapter Bameh Ishah; Sma"g; Hagahos Maimoni; Tur]
11. When a bath whose vents through which the bath is heated were closed on Friday, it is permitted to bathe in [the warm water] immediately [upon nightfall] on Saturday night However, if its vents were not closed on Friday, even though by itself it was heated on Shabbat, one must wait at night (Saturday night) until the amount of time it would take to heat [the water] passes on Saturday night, because it is forbidden to do so by a decree, lest one stir the coals [to cause them to burn more effectively].
12. It is forbidden to enter a bathhouse [on Shabbos] even merely to break out in a sweat. [There are those who say that it is forbidden to even pass through a bathhouse in a place where one could break out in a sweat, (even when this is not one’s intent).] (Rashi and the Tur).
13. [The following laws apply] in a town in which both Jews and non-Jews dwell, and [the town] has a bathhouse in which people bathe on Shabbos; If the majority of the populace is non-Jewish, it is permitted to bathe in [the bathhouse] immediately [upon nightfall] Saturday night. If the majority [of the population] is Jewish, or even half, it is necessary to wait until the time it would take to heat the water passes on Saturday night.