Why is the use of electricity forbidden on Shabbat? Is the act of switching on an electric current that turns on a light, a fan, or some electronic device (such as a cellphone) forbidden by Torah law or by a rabbinical decree? What specific prohibition is involved?
In the hundred or more years that electricity has been in use, the subject has been discussed in halachic literature from all possible angles. Rabbi Yechiel Mechal Epstein, the rabbi of the city of Novharduk and the author of "Aruch Hashulchan," wrote in 5763 (1903) that "there is no electric power in most of our cities." But nowadays it is hard to imagine any technical activity without electricity, and this includes much more than lighting.
With respect to using electricity on Shabbat, a clear line is drawn between two types of devices: First are those which are defined as involved in "fire," where a majority of rabbis see a Torah prohibition involving "burning" and "extinguishing" (actually, putting a light out is only a rabbinical prohibition, since the action is what is defined as "labor which is not needed by itself"). In the second type of device, which includes the majority of electrical and electronic instruments in use today, there is no halachically defined "flame." "Electric fire" exists only where there is a heated filament, such as in a regular incandescent bulb or when using a heating element (even if this element is hidden from view). The rabbis of our generation all agree that operating such a device is prohibited by Torah law, defined as "a glowing ember of metal."
But what about the second category of device, without "fire"? What prohibitions are involved in using such equipment on Shabbat?
According to an innovative approach by the Chazon Ish (Shabbat 3:9), all electrical operations are forbidden as violations of the Shabbat labors "building" (boneh) or "giving the final touch in creating a vessel" (literally, makeh bapatish – striking with a hammer), since forming an electric circuit "activates its nature, allowing the electricity to flow continuously." In his view, allowing an electric current to enter a device that has been turned off "builds" it and returns the device "from death to life." Many of the rabbis of his generation disputed this definition, defining the use of an electric current as "utilization" and not as "creation." These rabbis felt that no Torah law is violated when an electrical device is turned on.
Rabbi Yitzchak Shmelkish (Responsa Beit Yitzchak, Yoreh Dei'ah, omissions 31) discusses the use of a telephone, which as noted above has no element of "fire." His innovative approach is that a telephone violates a rabbinical decree prohibiting the act of molid – giving birth, or making a new creation. An example of this prohibition is to grind up hail and snow in order to transform the resulting water into a river. Molid is a rabbinical decree and not a Torah law. This concept is based on the Talmud (Beitza 23), where it is prohibited to add a scent to clothing and dishes on Shabbat and holidays, because of a prohibition to "create an odor."
It should be noted that there is no problem in strengthening the odor of an article of clothing that already has a scent. Molid is defined as changing an item from one status to a completely different one, and it does not include increasing the strength of a property which already exists. This is the basis for allowing a change in strength of an existing current under certain circumstances (when no "flame" is involved).
In practice, it is generally assumed that electrical devices should not be turned on or off on Shabbat and the holidays but no specific attempts have been made to determine the basis for the prohibitions. If turning electrical currents on and off would be allowed, the appearance of Shabbat would be completely different than it is today, since almost anything can be accomplished today using electricity, and there would no longer be any apparent difference between Shabbat and the other days of the week. The discussions of the reasons for prohibiting the use of electricity are mostly relevant in boundary cases, such as medicine and where there are security concerns.
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