Texting on Shabbat involves the violation of a number of rabbinic prohibitions and perhaps some Biblical prohibitions as well. We will explore a few key technical issues, keeping in mind that there are others which we cannot discuss due to space limitations.
The treatment of electricity in halachah is complex. The accepted practice is to forbid adjusting electric currents on Shabbat, although there is a range of opinions as to why. Early discussions in the late nineteenth and early twentieth centuries explored various approaches to defining electricity within the categories of halachah.
The Gemara (Beitzah 23a) forbids, on a rabbinic level, spraying perfume on a garment on Shabbat because it creates (molid) a fragrance within the garment. Rabbi Yitzchak Shmelkes, in his responsa Beit Yitzchak (I:120:4) published in 1878, proposed that closing an electrical circuit, thereby causing electricity to flow through the wires, is similar to perfume entering fabric and also would fall under the rabbinic prohibition of molid.
Rabbi Shlomo Zalman Auerbach, in his 1935 work Me’orei Eish, disagreed with Rabbi Shmelkes based on an intimate understanding of the new technology and complex Talmudic arguments. A decade later, in 1946, Rabbi Avraham Karelitz published his Chazon Ish on Orach Chaim (no. 50) in which he forbade completing an electrical circuit because it constitutes the forbidden labor of building (boneh).
The consensus today seems to follow Rabbi Yosef Eliyahu Henkin’s middle approach found in his 1945 work Eidut LeYisrael (nos. 20,56): unless there are extenuating circumstances, we follow the strict views which completely forbid the closing of an electric circuit. When there are extenuating circumstances, we take into account the lenient views. Therefore, unless we are discussing a doctor or soldier using a cell phone or e-reader on Shabbat for his vital work, or some similar mitigating circumstance, we cannot permit the electronic use entailed.
Generating letters on a cell phone screen in almost all cases violates at least a rabbinic prohibition. The Biblical prohibition against writing on Shabbat only applies to permanent ink on parchment or ink and/or parchment equivalents. If one writes with fruit juice, which isn’t permanent, he violates a rabbinic prohibition. Similarly, writing in sand is only rabbinically prohibited.
Absent life-threatening danger, even intelligence operatives in the army must avoid texting on Shabbat.
Rabbi Shmuel Wosner (Shevet HaLevi 6:37), writing in 1983, ruled that creating letters on a computer screen is Biblically prohibited. The screen will not dissolve or rot and is therefore the equivalent of parchment. The letters also will remain on the screen permanently, unless someone actively erases them. However, Rabbi Nachum Rabinovich (Melumdei Milchamah , nos. 57, 63) argues that writing on a computer screen is not a prohibited form of writing because neither the letters nor the background is permanent. One will eventually turn off the electricity, causing everything to disappear, and even if one does not, the batteries or generator will eventually lose power and turn the computer off. Similarly, Dr. Avraham Sofer (Nishmat Avraham [2007, second edition], vol. 1, p. 569ff.) records that Rabbi Auerbach told him that writing via an electron stream is not considered writing with regard to the Biblical prohibition.
However, Rabbi Zalman Menachem Koren (Meorei Eish HaShalem , pp. 943-946) notes that a recently developed type of LCD, which includes the Kindle’s Eink technology, is problematic even according to these lenient views. With this technology, the molecules remain in place—the screen retains that which is written on it—even after being turned off. Writing on this type of screen would be Biblically prohibited because both the “ink” and the “parchment” last.
Cell phone screens present an additional issue. As previously mentioned, spraying perfume on a garment is forbidden on Shabbat because it creates (molid) a fragrance within the garment. While Rabbi Auerbach disagreed with the view that causing an electric current to flow is considered molid, he did not entirely reject the Talmudic concept. He argued that unrecognizable changes cannot be considered molid, but lighting a dark object, such as with a neon light, is rabbinically prohibited.
Applying this to cell phone screens, both CRT and plasma screens involve lighting pixels one way or another. Rabbi Auerbach would therefore consider their use on Shabbat rabbinically forbidden because of molid. LCD screens are backlit. If the backlight is already on, then using such a screen only blocks or modifies light and does not turn it on. Therefore, molid does not apply to LCD screens unless one turns on the backlight. However, cell phones never maintain a constant backlight because of the battery drain. Therefore, using even LCD screens is rabbinically forbidden, according to Rabbi Auerbach, because of molid.
There are other issues worthy of mention, such as texting indirectly (grama), texts being automatically saved to a server which might be prohibited and the parameters of the somewhat ambiguous prohibition of performing a “weekday activity” on Shabbat (uvda dechol), which we cannot explore here. However, an important responsum by Rabbi Rabinovich (ibid.) places a worthy emphasis on the entirety of halachic arguments on this subject.
Rabbi Rabinovich was asked by his students in the IDF whether when writing non-urgent security-related information on Shabbat they should type on computers or write with special Shabbat pens with slowly disappearing ink. After extensive consultation with IDF engineers, Rabbi Rabinovich ruled that the otherwise rabbinically prohibited pens are halachically preferable to electronic writing on a computer screen. Absent life-threatening danger, even intelligence operatives in the army must avoid texting on Shabbat.
Rabbi Gil Student writes frequently on Jewish issues and blogs at TorahMusings.com. This article is an abbreviated version of a longer study Rabbi Student will shortly publish on this topic.