Shabbat 3:48

['With regard to a stove that was lit on Shabbat eve with straw or with rakings, scraps collected from the field, one may place a pot of cooked food atop it on Shabbat. The fire in this stove was certainly extinguished while it was still day, as both straw and rakings are materials that burn quickly. However, if the stove was lit with pomace, pulp that remains from sesame seeds, olives, and the like after the oil is squeezed from them, and if it was lit with wood, one may not place a pot atop it on Shabbat until he sweeps the coals from the stove while it is still day or until he places ashes on the coals, so that the fire will not ignite on Shabbat. Beit Shammai say: Even after one has swept away the coals, it is only permitted to place hot water on it, as it is sufficiently hot and does not require additional cooking, but not cooked food. Since, in general, one prefers that food will cook more, there is concern lest he come to ignite the fire by stoking the coals. And Beit Hillel say: Both hot water and cooked food may be placed. Beit Shammai say: One may remove a pot from the stove on Shabbat but may not return it. And Beit Hillel say: One may even return it.', 'The halakhot that were stated with regard to a stove were specific to a stove’s unique structure and the manner in which it retains heat. However, with regard to other baking apparatuses, i.e., an oven or a kupaḥ, there are different rules. The mishna delineates: An oven that they lit even with straw or rakings, one may neither place a pot inside it nor atop it on Shabbat. Whereas a kupaḥ that was lit with straw or rakings, its legal status is like that of a stove, and one is permitted to place a pot atop it on Shabbat. If it were lit with pomace or with wood, its legal status is like that of an oven and it is prohibited to place a pot atop it on Shabbat.', 'In addition to the halakhot that deal with cooking on the fire on Shabbat, several related halakhot are discussed. The mishna says: One may not place a raw egg next to an urn full of hot water so that it will roast slightly. And one may not even wrap it in cloths, i.e., one may not heat the egg inside cloths that were heated in the sun. And Rabbi Yosei permits doing so in that case. And, similarly, one may not insulate it in sand or in road dust that was heated in the sun so that it will roast. Although there is no actual cooking with fire here, it is similar to cooking and the Sages issued a decree to prohibit doing so.', 'The mishna relates a story about the people of the city of Tiberias, and they ran a cold-water pipe [silon] through a canal of hot water from the Tiberias hot springs. They thought that by doing so, they could heat the cold potable water on Shabbat. The Rabbis said to them: If the water passed through on Shabbat, its legal status is like that of hot water that was heated on Shabbat, and the water is prohibited both for bathing and for drinking. And if the water passed through on a Festival, then it is prohibited for bathing but permitted for drinking. On Festivals, one is even permitted to boil water on actual fire for the purposes of eating and drinking. In this mishna, the Sages discuss two vessels used for heating water. With regard to a mulyar, a bronze vessel into which coals are placed in an outer compartment and water is placed into an adjacent inner compartment, whose coals were swept, one may drink from it on Shabbat. With regard to an antikhi, which is a vessel with a different configuration, even if its coals were swept, one may not drink from it on Shabbat.', 'The Sages added to the laws of leaving food on a source of heat and cooking food on Shabbat: An urn that was emptied of its hot water on Shabbat, one may not place cold water into it so that the cold water will be heated. However, one may place cold water into an urn or into a cup that were emptied of their hot water in order to warm it but not in order to heat it. In continuation of the discussion of vessels where the prohibition of cooking applies even though the vessels are not actually on the fire itself, the mishna establishes: A stew pot [ilpas] and a pot that were removed from the fire while they were still boiling, even if they were removed before Shabbat, one may not place spices into them on Shabbat itself. Even though the pot is not actually standing on the fire, the spices are still cooked in it because the pot is a primary vessel, i.e., a vessel whose contents were cooked on the fire. However, one may place the spices into a bowl or into a tureen [tamḥui], which is a large bowl into which people pour the contents a stew pot or a pot. Bowls and tureens are both secondary vessels and food placed into them does not get cooked. Rabbi Yehuda says: One may place spices into anything on Shabbat except for a vessel that has in it something containing vinegar or brine of salted fish.', 'From a discussion of the halakhot of insulation and preparation for Shabbat followed by a brief tangent dealing with the prohibited labor of cooking on Shabbat, the mishna proceeds to briefly discuss prohibitions relating to set-aside [muktze] items in terms of Shabbat lamps. One may not place a vessel beneath the oil lamp, the vessel containing the oil and the wick, on Shabbat in order to receive the oil that drips from the wick. And if one placed the vessel on Friday while it was still day, it is permitted. However, in any case, one may not make use of the oil on Shabbat because it is not from the oil prepared from Shabbat eve for use on Shabbat. The oil in the lamp was already set aside and designated solely for the purpose of lighting the lamp. The dispute in this mishna seems to be a local one; however, it is the key to several halakhot in the area of the prohibition of set-aside [muktze]. One may move a new oil lamp on Shabbat but not an old one that was already used. A lamp that was used is covered with soot and unsuitable for use. It is therefore considered set aside from use due to its disgusting nature. Rabbi Shimon says: All oil lamps may be moved on Shabbat except for an oil lamp that is burning on Shabbat, due to the concern that it might be extinguished. One may place a vessel beneath the oil lamp in order to receive burning sparks of oil that fall from the lamp so that they will not cause a fire. And he may not place water into the vessel because he thereby extinguishes the sparks. When a pot is removed from the fire on Shabbat eve it may be insulated in materials that preserve its heat, but not in materials that increase its heat. Raising the temperature of a pot is tantamount to cooking. ']