shabbos candles

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 Semicha Program

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


Questions for the Week of Parshas Va'erasubscribe


Can I spread mayonnaise or butter inside a boiling hot potato?

A concept, borrowed from Issur v’Heter 1, which says that a hot solid remains a k’li rishon even after being placed in a k’li shaini or shlishi. Accordingly, the rules of cooking inside a k’li rishon apply themselves to a potato as well. Since mayonnaise has not been cooked, it may not be put inside a hot potato. Butter on the other hand is made from pasteurized milk, which some poskim recognize as being cooked. Rav Moshe Feinstein 2 Ztz”l says that it is permitted to put butter inside a hot potato, but Rav Shlomo Zalman Auerbach 3 Ztz”l says that it is not permitted, as butter has not been cooked in its present state.

On the exterior of an electric urn is a small transparent pipe, which gets filled with water. When opening the tap, the water in that pipe enters the urn and mixes with the boiling water, is there anything to be aware of?

The problem is that the water in the pipe is not fully cooked. Although it is close to or above yad soledes bo, but it has not boiled, and by admitting the water into the urn, it will probably boil, thereby being liable for the issur of cooking 4. However, before using it, one should refer to a competent Rav for guidance.

If a light was unintentionally turned on, may one benefit from it?

It is prohibited from the Torah to switch on a light on Shabbos due to the filament inside the light bulb. The Chazon Ish also added that one is also liable of “Boneh – constructing”. Therefore, when a light is switched on, a Torah prohibition has been transgressed, and the halacha is as follows: The Shulchan Aruch 5 prohibits deriving any benefit from the issur until after Shabbos. The Vilna Gaon, however, holds like the opinion that one may derive benefit from the issur on Shabbos itself. (This only applies to an unintentional transgression of an issur). The Mishna Berura rules in accordance with the Shulchan Aruch but adds that in special cases, the lenient opinion can be relied upon.

Rav Shlomo Zalman Auerbach Ztz”l held that “necessary” means that there is no other option available. In other words, it is not to be taken lightly and a Rav should be consulted!

Is there a difference between turning a light on without thinking and turning it on without noticing (i.e. by leaning on the light switch)?

Without thinking is called b’shogeig – unintentional, and without noticing is called misaseik. There is a big difference between the two. For the former one is required to bring a sacrifice (if a Torah prohibition was transgressed), for the latter there is a possibility that one is required to do teshuvah – repent.

If when walking into a room on Shabbos, one ‘forgets’ what he is doing and turns on the light, it is a shogaig, and one is required to bring a sacrifice to the Beis HaMikdash. If one leans on a wall and accidentally turns on the light, it is a misasek; some say repentance is required, although it is not the same as a shogeig.

The stone on my porch becomes very hot from the sun, am I permitted to warm food on it?

The halacha is that food may be warmed from direct sunlight, but is forbidden to be warmed from the sun’s derivatives. Therefore it is forbidden to warm an egg by placing it on the stone, but heating it in direct sunlight, is permitted.

[1] In Yore Deah we find a machlokes between the poskim as to whether it has a status of a k’li rishon or shaini. The M”B is stringent in this aspect.
[2] Iggros Moshe Orach chaim 4, 74-6.
[3] Sh’miras Shabbos Kehilchasa 1:55
[4] Minchas Yitschak part 10-28.
[5] Siman 318:1

Food For Thought

If one did hatmana b’issur (enwrapped in a forbidden manner) is the food forbidden? For example, if I completely enwrapped the chalah while it was on the urn, am I permitted to eat it?

If food on the blech or hot plate is beginning to burn, may I stir the food?

Is there a difference between stirring food when it is on the fire and when it is off the fire?

Vort On The Parsha

The possuk says (8-2) that the frog came out and covered the land of Egypt. Rashi brings the Midrash saying that only one frog came out of the water and the Egyptians beat it, which subsequently spewed forth swarms of frogs.

Rav Ya’akov Yisroel Kanyevsky Ztz”l (The Steipler) points out that had the Egyptians had any sense, they should have stopped beating the frog and the entire vicious plague would have been avoided. The reason they continued is because of human temperament; just as two people get into an argument, and as the possuk in Mishlei (15-1) says “replying softly will arrest anger”, if one of them will talk softly the argument will end, but nevertheless human nature says: “fight, show him!”, so too the Egyptians would not stop and think that they are bringing a catastrophe upon themselves.

For a printed version, click here.

In memory of HaRav Chaim Kreiswirth ZT"L

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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.