Reading by electric light on Shabbos

Hi,

The Talmud (Shabbat 12a) records a prohibition against reading by an oil lamp, lest one forget it is Shabbat and incline the lamp to provide fuel for the wick. This is brought in Shulchan Aruch. (Orach Chaim 275:1)

This concern does not apply regarding a light bulb fueled by electricity, because the light is generally great enough that one will not need to adjust, and because there is no means of adjusting it to raise its luminescence. However, it is not clear that this permission should extend to a bulb which has multiple settings.

(Rivivot Ephraim 1:222:27)

Have a great day,
Mordechai

An electric blanket on Shabbos

Hi,

One may use an electric blanket on Shabbos, where it is already on, but one may neither turn it on nor adjust the setting.

(Rivivot Ephraim 1:222:26 and 1:235)

Have a great day,
Mordechai

Voice-activated recording on Shabbat and Yom Tov

Hi,

Speaking, and thereby activating a voice-activated recorder, is prohibited on Shabbat and Yom Tov, even where one does not intend to activate the recorder, where that is a guaranteed result of one's speech.

(Rav Moshe Feinstein, Igrot Moshe Yoreh Deah 1:173)

Have a great day,
Mordechai

Electric appliances on Shabbat

Hi,

Electric appliances are not considered a kli shem'lachto l'issur [an implement which is normally used for Shabbat-prohibited purposes] by dint of its electric current. It is only considered a kli shem'lachto l'issur if its function is to be used for Shabbat-prohibited tasks [i.e. a hair dryer, as opposed to a clock].

(Rav Moshe Feinstein, Igrot Moshe Orach Chaim 5:23)

Have a great day,
Mordechai

Electricity and kli shem'lachto l'issur

Hi,

The fact that an item has an electric light attached to it does not automatically render the item muktzeh; where there is no likelihood that one would turn off the light (such as a light illuminating the face of an electric watch, or a light that indicates an urn is operational) then the light does not render the item muktzeh.

(Rav Moshe Feinstein, Igrot Moshe Orach Chaim 5:21:4)

Have a great day,
Mordechai

Hearing aids on Shabbat

Hi,

We are lenient regarding use of a hearing aid on Shabbat. This is different from use of a microphone:

With a microphone we are concerned that people normally connect it only when they need it, so that people will assume it was turned on during Shabbat, but that concern only applies regarding items which make noise, calling themselves to the attention of the public.

The concern of "don't use it lest you adjust it" which we express regarding microphones also applies regarding hearing aids, but a) that is a rabbinic decree and so it may not apply to the uncommon case of a hearing aid (for rabbinic decrees were created only for common cases), and b) the hearing aid involves great need, such as to hear an oncoming car. However, one should do something to prevent actual adjusting.

As far as the concern that one activates a microphone to create a new voice when he speaks, and so one is finishing its construction (makeh b'patish) or actually building it (boneh), neither of these is clear-cut, and this is a case of great need, as we have explained. [There is more here in Rav Moshe's discussion.]

As far as the concern that one's voice causes the electrical current to rise or fall, the prohibition involved is not clear, and this is a case of great need.

Further, sometimes the hearing aid does not pick up the sound, and so its activation is not a guaranteed result of one's action.

Further, if one speaks to people in general, and not only to the person with the hearing aid, then one does not intend to activate it. Indeed, ideally one should avoid speaking to him personally, if at all possible.

(Igrot Moshe Orach Chaim 4:85)

Have a great day,
Mordechai

Microphones on Shabbat

Hi,

There are four main reasons to prohibit speaking into a classic microphone on Shabbat:

Causing a microphone to broadcast a sound via its reaction to one's voice may involve completing the microphone's functionality or building it, which would be biblically prohibited;

Causing the electrical current to rise and fall may involve biblical prohibitions, even though the circuit remains "on" throughout the operation of the microphone;

We may not engage in activities which appear to be prohibited ("marit ayin"), and since microphones are normally turned on only when needed, listeners may not realize that this sound system was turned on before Shabbat;

If the sound system were to malfunction, one might forget it is Shabbat and adjust it.

(Rav Moshe Feinstein, Igrot Moshe Orach Chaim 4:84)

Have a great day,
Mordechai

Electric blankets on Shabbat

Hi,

One may use an electric blanket on Shabbat, assuming it was turned on before Shabbat. One may not adjust the temperature, though. One must also cover the controls as a reminder to keep him from adjusting them, and one must do something similar at the outlet as a reminder not to unplug it.

(Rav Moshe Feinstein, Orach Chaim 3:50)

חג אורים שמח,
Mordechai

A light which a Jew will extinguish on Shabbat

Hi,

One may not turn on a light before Shabbat, even for a mitzvah like prayer, if he knows that a Jew will turn it off on Shabbat. However, one may turn it on if he is uncertain whether a Jew will turn it off.

(Rav Moshe Feinstein, Igrot Moshe Orach Chaim 3:43)

Have a great day,
Mordechai

Entering a hotel room with an electronic key

Hi,

May I have a non-Jew open my hotel room with an electronic key on Shabbat?

Most authorities rule that use of such a key violates at least rabbinic law, and so one may not tell a non-Jew to use it on Shabbat. Further, one may not benefit directly from melachah performed by a non-Jew on Shabbat. However, leniencies are offered for a case of need:

• I may tell the concierge, upon checking in, that this service is required in order to make my stay possible. When he makes the arrangement, it is with his own good in mind.

• If a non-Jewish hotel employee opens my door on his own, without any instruction, I may enter the room if necessary. This is because my benefit is considered 'indirect', and because the employee does it with his own good in mind. Some suggest actually keeping a gift for the hotel employee in the room and telling him you have something for him [without actually requesting he open the door], so that he opens the door for his own benefit.

Note that the hotel key itself may be considered "muktzeh", and should not be handled by the Jew.

(Beer Moshe 6:Kuntrus Electric 19; Melachim Omnayich pg. 575)

Have a great day,
Mordechai