Shulchan Aruch Chapter 253:  The Law of Putting Pots On A Double Stove and A Single Stove on Erev Shabbat
(5 Paragraphs)
REMA in Brackets []

Introduction to this chapter:  One of the forbidden acts of labor on the Sabbath is cooking.  In order to eat hot food on the Sabbath, Jews prepare food on Friday and leave these foods on the stove to continue cooking on Shabbat.  Until modern times, there were two types of stoves used for cooking.  One was a Tanur, which was a stove with a single opening on top, where one pot was placed.  The interior of the stove was heated with wood or other items, and one could also place items in the oven itself.  Since all of the stove's heat was concentrated in one spot, it was considered a very hot stove.  Another type of stove was a Kirah, or a double stove.  This had two openings on top for two pots.  The interior was also heated with wood or other items.  This was not a very hot stove.  The Rabbis at the time of the Mishnah were concerned that on Shabbat, perhaps a person may accidentally stir up the embers in the oven in order to produce more heat so that the item will cook better.  So, to prevent this from happening, they enacted restrictions on what type of stove one may use on the Sabbath to keep food on, what foods may be put on, what the stove can be heated with, and how the heating elements may be modified for use.

1.  The definition of a double stove (Kirah) is a stove constructed with two openings on top where you can put two pots.  If this stove is heated with marc, meaning leftover byproducts of olives, or if is heated with wood, then it is prohibited to put food to cook on it before the Sabbath so that it would continue cooking on the Sabbath.  An exception would be if the food was entirely cooked and it is Mitz'tamek [meaning going further would cause a loss], in that it would be bad for the food (to cook it further), for in this case we are not worried maybe he will stir the coals.  Another exception would be if the food was entirely raw, and completely uncooked.  Since it is raw, he does not pay any attention to it until the next day.  Such an item is able to be cooked all night long without stirring the coals.  However, if the food was cooked a little but not cooked entirely, or it was cooked entirely, but cooking it longer will benefit the food, we are worried that perhaps he will stir up the coals.  So, such an item is prohibited to put on the stove unless he sweeped it, meaning removing all of the coals, or if he smothered it, meaning covering the coals with dirt in order to reduce their heat.  If one put in a raw piece of meat, it is permitted as long as it is entirely raw, since he doesn't pay attention to it.  This applies even if it was not raked [meaning, the coals removed] or smothered [meaning covered with dirt] and it is permitted to place a pot next to it.  If the stove was heated with straw or with stubble then it is permitted to leave all items to cook on it, even if the fire was not raked or smothered [1].  [Consider the case where there are two double stoves joined together with a wall of pottery between them.  One was sweeped and smothered, and the second stove was not sweeped or smothered.  It is permitted to leave food in the one that was sweeped or smothered even though it increases the heat in the one that isn't sweeped or smothered.] 

A single stove (Tanur), even if it is heated with straw or stubble can not be used.  This applies even for putting food on it (not on the burner) and even if it was raked or smothered [in any case where the heat is enough to burn one's hand].  Certainly it is prohibited to leave food inside it or on the burner.  A Koopach [2] that has room for only one pot, if it was heated with straw or stubble, the law is like a double stove, if it was heated with wood or mark then the law is like a single stove [our single stoves have the same law as a double stove].  If one forgot the law and left food on it, if it was entirely cooked then it is permitted even if it would benefit the food from cooking more.  If it was food that began to cook but was not entirely cooked, then it is prohibited to eat until after the Sabbath.  If one purposely violated the law and left food on it, then both are prohibited.  [Meaning until the time it would take for it to be made (one must wait after the Sabbath to eat it).  If a Gentile put the item back on the stove on the Sabbath, the law is the same as if he forgot and left it.  If a Jew put the food back on, the same law applies as if he purposely violated the law and left food on it.  If the food was fully cooked and cooking it longer would be bad for the food, it is permitted since he would not benefit from the violation, see later in the beginning of ch. 257.] 

Some say that anything that is cooked like the food of the Son of D'rosai [meaning a certain person who wood eat only minimally cooked food] or if it was entirely cooked and cooking it longer would benefit it, then it is permitted to leave it on a single stove (Tanur) [or even on a double stove (Kirah)].  This is true even if it was heated with mark and wood and even if it wasn't raked or smothered.  In fact, raking and smothering is not relevant with straw and stubble unless the food began to cook and did not yet reach the level of the Son of D'rosai [3].  If he put the pot on the stove and left it there on the Sabbath, but he forgot and left food that began cooking but did not yet reach the level of the son of D'rosai, then it is prohibited.  It is not necessary to repeat the case of if he purposely violated the law and left it [our custom is to be lenient like the second opinion]. 

All the following are in the category of leaving (an item to cook in the oven) [4]: if the pot was placed on an iron stand or on stones but they do not touch the coals.  However, insulating the food by putting the pot directly on the coals is prohibited according to everyone.  [Some say that even if the pot is sitting directly on the fire, so long as it is uncovered on top is not considered insulating and is permitted.  Such is the custom.  However, one should be careful in order to move it a little from the fire before the Sabbath in order that a Jew can remove it.  If it was not moved from the fire and was found directly on the fire on the Sabbath, one can move it from there through a Gentile.  If there is no Gentile available, then it is permitted for a Jew to remove it from there, but be careful to do this slowly to not move the coals, then even if he moves the coals a little, it is something that is not intended and permitted.]

2.  A double stove that was sweeped or smothered and a pot was removed from it, one is allowed to put it back even on the Sabbath, so long as it is hot [still in his hand] and was never put down [and he intended to put it back].  This is only for putting it on top of the stove, but inside the oven is forbidden.  In a single stove, this is prohibited.  For a single stove, one may not put items back even if it was sweeped and smothered, and the same applies to a mini stove if heated with wood or marc.   [This is only when the food is entirely cooked, only then is it permitted to put it back, even into a different double stove.  However, if it was not cooked entirely then it is prohibited, even in the same double stove.  Others say that all of this is not prohibited unless he removed it from the double stove when it is still day (on Friday) and did not return it until after nightfall.  However if he took it out after it was dark even if he put it down it is permitted.  Such is our custom to be lenient with our single stoves that have the laws of a double stove and rely upon the words of the lenient authorities. But it is good to be strict.  However, if it cooled everyone agrees that it is prohibited.]

Some say that if one takes out food from a single stove [on Shabbat] it is prohibited to put in in a double stove or in a mini stove.  Some say that in any case where it is near dark or near the Burchu blessing of the Kabalat Shabbat (greeting shabbat prayer) if it is so close that if he would remove the pot he would be unable to return it while it was still day the law is as if it was removed on Shabbat itself, these are lenient with this, and the custom is to be lenient, but it is good to be strict in a place where one does not need it so much.  This is only on a double stove, but to put it nearby, even near the fire in a place where the hand can be burned it is allowed even near dark.  And with a single stove there is no difference on putting it back on the stove or nearby, assuming it is a place where the hand can get burned (it is prohibited).  However if the hand can not get burned then it is allowed even on Shabbat as explained later in ch. 318.]

3.  Consider the case where one gets up in the morning to the sight of his food burning, and he is worried that perhaps it will continue to burn.  He is allowed to remove the pot and place another empty pot on the stove and then return the original pot with the food on top of the empty pot; but be careful that it is never placed on the ground and still hot.  [I already explained that our custom is to be lenient even if it was placed on the ground.]

4.  There are those who protest to those who have the custom to heat a kettle of water on Friday during the day then pour it into a pot with hot foot on the Sabbath.

5.  One is permitted to put on top the lid [6] of a pot with hot food cooking on the Sabbath food that was entirely cooked before Shabbat.  For example: pandish and similar items to warm since this is not considered cooking, but to put it on top of the food and insulate this with garments to heat it is certainly forbidden.  [Similarly it is forbidden to put them on top of a double stove even if it was sweeped and smothered, for they only allowed returning (food) in the way explained earlier.  Some permit putting the food (even) into a single stove where this stove was used for baking while it was still day (and left to cool), for if this is the case there is no longer any flame left in it and we are not concerned that this could cook an item.  However, this only applies when the item is not heated up completely.  Some are strict with this.  If the single stove is capable of warming an item to the extent that it could burn the hand, then this is prohibited; see later ch 318.  All activities stated above that are forbidden are also not allowed to tell a Gentile to do them.  It is similarly prohibited to tell a Gentile to heat a pot of food that cooled, and if this was done it is forbidden to eat it, even after it cooled.  However, if the food did not cool that much, so that it can still be eaten then it is permitted to eat it if a Gentile heated it up.  Therefore, some have the custom for gentiles to take out a pot from a single oven where it was (left) to keep warm then they put next to the top burner [5] on a single stove or on top of it then afterwards they heat up that oven and warm (the food).  It is not permitted for a Jew to do this.  However, if the pot is still hot one may put it next to the top burner after we have already explained that our single stoves have the law of double stoves.  And putting it on a double stove that was not sweeped or smothered has the same law as one that was sweeped or smothered with regard to putting things back on it, also we explained that our custom is to be lenient with regard to returning pots on the Sabbath even if they were placed on the ground.  The same law applies to a single stove that was not sweeped and smothered since the pot is already hot and cooked entirely.  Therefore the simple custom is to permit it, see later ch. 318].

Footnotes:
1.  Straw and stubble are consumed quickly and do not form embers or coals when used in a double stove.  Therefore, there is no concern that one will stir up the coals on the Sabbath.
2.  A type of small stove.
3.  Meaning according to this lenient opinion, if the food did not yet cook enough for the Son of D'rosai then one must rake out the straw or smother it in order to leave the food to cook on the Sabbath.
4.  Before, when we discussed leaving food in the oven, it means placing the pot not directly on the coals, but through indirect contact like with an iron plate.  In modern times, Jewish homes leave a metal plate (called a Blecht in Yiddish) on top of the burners and place pots with food on this metal plate before the Sabbath.  Usually one fire is left on low. 
5.  Unsure of exact meaning, this word usually means winter but rarely can refer to an edge, which the closest meaning here is probably the opening on top of the stove, or burner
6.  Literally "on the mouth" of a pot.
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Translated by Jay Dinovitser 01/2013.
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