Heating on Shabbat in an Aluminum Pan; Ribbit Between Sisters

Hello, honored Rabbi,

1. I do not have a Shabbat hotplate. May I place the dish before Shabbat in an aluminum pan on four upside-down cups, with two yahrzeit candles underneath them, in order to keep the food warm until Shabbat afternoon?

2. I lent my sister laundry detergent, and she returned to me capsules in an equivalent quantity, but they are more expensive. We are not particular with one another. Is there any concern of ribbit in this?

Thank you very much.

Shalom u’vrachah 

1. This is considered an exposed fire, and not “gerufah u’ketumah” — raked out and covered. Therefore, it is permitted to place the dish this way only if it is fully cooked before Shabbat. 

All of this applies when the cooked food is in the pan itself. However, if one places the food inside a utensil, and in addition to this utensil places an aluminum pan underneath the utensil, so that the heat is reduced by the pan, this is considered “ketumah,” covered, and it is permitted to leave it there in this manner. 

2. If there is not a large difference in price, it is permitted if you are not particular with one another. 

If there is a large difference in price, it is forbidden. She should pay you the estimated price of the detergent she took. 

Have an additional question on this topic or need clarification? Leave your comment below. (Please note that the comment will not be published but will be sent directly to the answering Rabbi for review and a private response)