Siman 253 – Leaving / returning food to cook on the stove
There used to be a stove (called a kira) that was shaped like a shoe box with room for two pots. It was heated with coals. Chazal were worried that you may come to stoke the coals if you leave (SHEHIA) the pot to cook on Shabbos, unless:
The food is fully cooked (or water fully heated) and it will get worse if heated more.
The food is still raw just before shkia and will not be ready for the night meal even if heated more.
You sweep out the coals before Shabbos.
You cover the coals with something that cools them down – or coals have not been stoked (they have darkened) – this shows that you are not concerned about their heat.
You put in a piece of raw meat just before shkia. (ShA1 – MB9,10,12,14 – BeH “tavshil”)
If neither one of the five conditions exists, you must remove the pot from the stove before dark. (MB5)
The above prohibition applies l’chatchila even if you don’t need the food until the day. You can rely on a lenient opinion, Bedieved. (BeH “l’hash’hoso”)
If you do not know if the fully cooked food will get worse if heated more or not, be strict. (BeH “v’hu”)
In a case that unexpected guests arrive before Shabbos and you need to cook more food, you can rely upon the lenient opinion that allows to quickly put up a pot and let it finish cooking directly above the coals on Shabbos. One condition: the food must be at least k’maachal ben derusui before Shabbos – that is half cooked (if it's pressing, a third cooked) which makes it barely fit to eat. (BeH “v’nohagu” –MB38)
To leave the pot of food next to (SMICHA) a kira on erev Shabbos is not restricted at all. This is even when the heat that emanates is yad soleddes. Some poskim allow smicha even on Shabbos, as long as the pot is still hot and the contents are fully cooked. (i.e. the food can’t be cooked further). (ShA1 – MB15,17)
If the place that you want to put down or leave a pot isn’t yad soleddes, there are no restrictions or pre-requirements. (MB23)
If you do not follow these rules there are cases that make it forbidden to eat the food so as not to benefit from the avaira: The food was not yet a third cooked and you left it cooking on purpose, no one eats it until Motzo'ay Shabbos after waiting the amount of time it takes to cook it. If you left it by mistake you can be lenient and eat it right after Shabbos. (ShA1 – MB32,43)
Here’s the case: You left a fully cooked pot surrounded by coals. You need the food for Shabbos night. You may not move the pot out because the coals will move and that causes some to go out and others to get stoked. Even though it’s not your intention, it’s still a p’sik raysha. But since you don’t care about the coals, it’s lo nicha lay. So the worst it can be is ossur d’rabbonon. There is an argument if you can ask a non-Jew to remove the pot from the coals. For the needs of Shabbos you can rely on the lenient opinion – p’sik raysha al yeday aino-yehudi. (MB51, ShaH 43)
You aren’t allowed to put an already cooked food onto a hot kira on Shabbos. Even though there is no bishul happening, it appears like bishul since that is the surface that you cook on all week long. (MB55)
Under the following conditions the Chazal allowed you to remove and return (Chazora) a pot that was left on top of the kira from before Shabbos:
The kira’s coals have been swept out or cooled down with an ash covering from erev Shabbos.
Fully cooked – even though the food gets better the longer it cooks.
The pot hasn’t cooled down completely.
You never let go of the pot.
You had in mind to return the pot at the time you removed it. (ShA2 – MB55 – BeH “muttar”)
Bedieved, if you took the pot off without having in mind to return it, you can still return it. Also, if you did have in mind but you let go of the pot, you can put it back onto the kira – as long as you didn’t rest it on the floor. (MB56 – ShaH 50)
Chazora is allowed even to another kira that is hotter than the original one. (MB62)
You aren’t allowed to put food inside a hot oven (yad soleddes) for the first time even if the food is already cooked. Therefore chazora into a hot oven is also ossur if the food completely cooled down, even if the food is dry and totally cooked. (MB68)
If you did chazora (even by mistake) without fulfilling all the conditions, you aren’t allowed to eat the food (until Motzo'ay Shabbos) if the heat improved the food in any way. The Magen Avraham holds that other people can partake of the food as long as the food was fully cooked and chazora was by mistake. This penalty applies even if a gentile did the chazora for you. (Rama1 – MB35)
No penalty is imposed if the food (or hot water) gets worse as a result of the forbidden chazora . (Rama1 – MB36)
No penalty is imposed unless the chazora is ossur according to all opinions. (BeH “v’im”)
If the cholent is burning in the morning, you can remove it from the kira keeping to the above conditions, then place an empty pot on the kira. This will give the kira the status of “cooled down” so you can do chazora on top of the empty pot in order to keep the cholent warm. You can also transfer the cholent to the hot outside surface of an ignited oven. (ShA3 – MB81)
In the above ignited oven case, you should put a separation down before transferring the cholent. This hekker will allow you even to warm something at first (that wasn’t on the kira). Just be sure to avoid bishul – that if it is liquid that has totally cooled, do not warm it up. (MB81)
You are allowed to pour hot soup directly from the pot (kli rishon) onto cold cooked beans in a bowl. If the beans have some liquid, the Rama is lenient as long the liquid has not completely cooled. Even so, it is better to dole the hot soup using a ladle instead of pouring directly from the pot. (MB84 – ShaH80)
You are allowed to warm up food by placing it on top of a hot pot of water which is on a kira, but not directly on the kira. If the food has a lot of congealed fat with it, do not warm it up because the melted fat will be nolad. (ShA5 – MB87)
Insulating food to keep it warm (HATMANNA) is ossur on Shabbos. This is so even if the food is completely cooked and hot and even if the insulating material does not add heat. Therefore, in the above case of warming food on top of a hot pot which is on a kira, be sure not to wrap the food with a cloth. (ShA5 – MB88)
One way to warm food is to put it into a warm oven that is not yad soleddes. (MB92)
Amira l’nochri is forbidden even when giving an instruction to do an issur d’rabbonon. (ShAH94)
Another way to warm up completely cool food is to instruct a non-Jew to put the food on a (radiator or) furnace before igniting it. Then tell him to ignite the furnace. This is allowed since we are all in the category of ill when we feel cold – so amira l’nochri is suspended. Even though it is a p’sik raysha that the food heats up, its allowed through a goy. The action is deemed as heating the house. If the food would be on a surface which serves also to cook, this strategy wouldn’t work. The goy’s intention would be also to warm the food which deems the action as warming the food. (Rama5 – MB99)
It is forbidden for the Jew to put the cold food on the cold furnace and then instruct the goy to ignite the furnace. (Rama5)
When washing cold greasy dishes with hot water on Shabbos, do not pour the water directly onto the dishes – that action melts the grease and becomes nolad. Rather put the dishes into the hot water. (MB100)