shabbos candles

The Shabbos Weekly
Halachos Series on Hilchos Shabbos

shabbos candles

Published by
Pirchei Shoshanim

A Project of
The Shema Yisrael Torah Network

Based on the Shiurim Given by

Rabbi Dovid
Ostroff, shlita

developed from the Chabura of the
Pirchei Shoshanim Shulchan Aruch Learning Project

These Halachos were shown by Rabbi Ostroff to
HaGaon HaRav Moshe Sternbuch, shlita



Questions for the Week of Parshas Toldos

If a Jew accidentally cooked on Shabbos, may the food be eaten on Shabbos?

From a customary perspective it would seem a bit far fetched to envisage a frum Jew cooking on Shabbos, so what’s the issue? Firstly, as will soon be described, it is indeed possible. Secondly, this applies to all Shabbos violations such as performing prohibited borer (separating), or accidentally switching on lights.

Please provide an example of accidental cooking.

A classic example: the halacha states that food is susceptible to the prohibition of cooking prior to being fully cooked, [1] - which means; one may not move a pot of food – which is not yet fully cooked – to a hotter spot on the hotplate or blech; one may not cover such a pot of food with a towel or any covering, [2] because both activities hasten the cooking process.

If one removed the lid from the pot of food and discovered that the food is not fully cooked, it may not be returned to the pot for any money in the world, as it will cause a Shabbos violation of cooking. [3]

An even grosser violation would be pouring boiling water from an urn onto a teabag.

So what’s the answer?

We find a machlokes [4] between R’ Yehuda who holds that one who did a melacha accidentally (b’shogeig) may not consume that food until after Shabbos. The prohibition includes the person responsible and others. R’ Me’ir holds that he and others may consume the food on Shabbos.

The Shulchan Aruch rules [5] in accordance with R’ Yehuda (in wake of most Rishonim). The Vilna Ga’on rules [6] in accordance with Tosafos who sides with R’ Me’ir.

The Mishna Berura arbitrates between the two rulings and states that in normal circumstances we follow the opinion Shulchan Aruch, meaning the food may not be consumed until after Shabbos. When necessary for the sake of Shabbos, one may rely on the Vilna Ga’on and consume the food on Shabbos as well.

But we have not finished yet.

It is imperative to know that in the cases above, when food was pushed closer to the hotspot or the pot was covered, if the food was cooked more than ma’achal Ben Derosai [7] beforehand one may consume the food on Shabbos even though a prohibited act was performed.

This is different to tealeaves that were not cooked at all.

How would you define “necessary for Shabbos”?

If one can easily manage without that dish or beverage, it is not “necessary for Shabbos”. For example, one poured boiling water onto tealeaves, thereby cooking them, as stated. In most cases one is able to substitute tea with another beverage and/or one can make another tea in a permitted manner. It is hard to envisage that tea made in a prohibited manner as “necessary for Shabbos”.

Or if potato kugel was cooked b’issur, either by covering it or pushing it closer to the hotspot before fully cooked, if it serves the main diet at the Shabbos table, it would be “necessary for Shabbos”, but if there is ample food without it, it would not be “necessary for Shabbos”.

May one benefit from a light switched on Shabbos?

It depends who switched it on and why.

If a Jew switched it on for the sake of pikuach nefesh, we learned that one may benefit from it as there is no concern that more light will be switched on for the ill person’s benefit. [8]

If a Jew switched it on accidentally, based on the above it may only be used when “necessary for Shabbos”, which is hard to visualize, because one intended on managing fine that Shabbos without it.

If a Jew switched it on deliberately, it may not be used by anyone that Shabbos.

The following has indeed happened: a religious person was walking down a dark stairway in a building when a ‘kind’ neighbor felt sorry for him and switched on the lights. Our friend may not use those lights, being that they were switched on deliberately on Shabbos and he may not do anything that he could not do before. He may obviously continue down the stairs but he my not hurry and take advantage of the lights because they were switched on b’issur (in a prohibited manner).

What if the mechalel Shabbos switched it on for himself?

The same rule applies, because they are turned on b’issur.

May an adult benefit from a light switched on by a child?

It depends on the child’s intention. If the child switched it on for his own benefit, [9] an adult may benefit from it, [10] but if he switched it on for an adult, one may not benefit from the light.

What if a light was switched on unknowingly?

If one leans on a wall without realizing that a light switch is there or was pushed against it, the Oneg Yom Tov simon 20 writes that one may not benefit from the action. The reason being that Chazal did not make a distinction between an unintentional violation and the above case called mit’aseik.

[1] Simon 318:4.

[2] Simon 257:4.

[3] There are poskim who prohibit returning a lid to a pot even when the food is fully cooked.

[4] Chulin 15a.

[5] Simon 318:1.

[6] M”B simon 318:7 and Bi’ur Halachaachas’.

[7] A machlokes between Rashi and Rambam as to whether it means food is ½ cooked or 1/3 cooked.

[8] Simon 318:2.

[9] There is a chinuch (teaching) issue, which is not addressed at this point, of whether one must teach one’s child or another person’s child Shabbos prohibitions.

[10] Bi’ur Halacha simon 325:10 ‘eino yehudi’.


Food For Thought

May one use a light turned on by a gentile?

May one enter a door opened by a key carried through a reshus harabim?

May a Jew enter an electronic door opened by a mechalel Shabbos?

Answers coming be"H next week.

Vort on the Parsha

Yitzchok accused Avimelech and his people of hating him and sending him away. To this Avimelech replied that we did not ‘touch’ you and only did good, which does not seem to answer Yitzchok’s accusation.

The commentators answer that Avimelech was telling him that for a Jew to escape unscathed from the hands of evil goyim is ‘very good’ and he should not complain.

For a printed version, click here.



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Note:  The purpose of this series is intended solely for the clarification of the topics discussed and not to render halachic decisions. It is intended to heighten everyone's awareness of important practical questions which do arise on this topic.  One must consult with a proper halachic authority in order to receive p'sak.