Shabbat 37: Rabbis Chime in on Cooking on Shabbat

The Gemara continues to discus a pot put on a stove that is burning on Shabbat.  Hillel had said that it is permitted to place cooked food on the stove and that one can remove and put back that pot of food during Shabbat, even if the food might cook further.  Shammai said that one must be careful about what is fueling the flames and that a pot once removed from the stove cannot be returned.  Other rabbis take sides on this argument, too.  There is concern that unswept ashes might be stoked or rekindled.  Our rabbis create fences around fences to ensure that we are not lighting fire on Shabbat.

Must food become worse while left on the stove for that action to be permitted?  We are reminded that breads and cakes cannot be baked on Shabbat; their crusts must be finished before Shabbat begins. The rabbis note that some crusts crack and become smaller over time.  Examples are provided of people bringing food for great rabbis who were ill on Shabbat.  If that food becomes less appetizing over time, like fried fish, everyone agrees that it may be left on a stove while it "shrivels and deteriorates".   If the food shrivels and becomes better, the rabbis have mixed opinions.