6. Hearing Aids
Contemporary poskim have permitted the use of hearing aids (which are actually small microphones and amplifiers) on Shabbat, and were seemingly unconcerned with the problem of electricity.
The Tzitz Eliezer (vol. 6, 6:6) summarizes:
From all the above, it seems in my humble opinion that it should certainly be permitted for a hearing-impaired person to use a hearing aid on Shabbat, provided it is turned on before Shabbat. There is no room to innovate a decree of mar’it ayin (an appearance of transgression); [in other words, we should not worry] based on the fear that others will see the hearing aid and think that it is permissible to turn it on on Shabbat. Just as we do not concern ourselves with appearances when a light is turned on or off by a timer (which was set before Shabbat), [so too here].
In his Responsa Minchat Yitzchak (vol. 1, 37), Rav Yitzchak Weiss dealt only with the issue of carrying a hearing aid on Shabbat; it seems that it was obvious to him that the electrical issues posed no problem. (He quoted Rav Yosef Eliyahu Henkin’s Responsa Edut L’Yisrael to this effect.) Later (vol. 2, 17) he was asked specifically why it should not be prohibited due to electricity; in what sense does it differ from a microphone? He responded that it was “unclear (safek) in reality and unclear in Halacha” whether there is hav’ara in a microphone. Therefore, “regarding the issue of microphones, I decided according to the stringent opinions, so as not to lead to breaches in the wall of the House of Israel [since those who wanted to bring microphones into synagogues were adopting untraditional modes of worship]. But regarding hearing aids – since those who use them do not intend to cause breaches, but rather to protect themselves from road hazards [and the like] – I relied on the lenient opinions, thinking that they certainly clarified that in fact there is no ground for suspicion [of hav’ara], as long as it was turned on before Shabbat.”
Subsequently, Rav Weiss cites the concurring opinion of Rav Ovadia Yosef (Yabia Omer 1:19), who says that Rav Shlomo Zalman Auerbach explained to him that “speech does not create any sparks, but rather a mere increase in current. And therefore we must conclude that it is permissible for one who is hard of hearing to place in his ear a device that amplifies sounds (as long as it is turned on before Shabbat), since there is no problem in increasing the current.” Rav Weiss repeated this opinion later as well (Minchat Yitzchak vol. 2, 112).
Rav Zvi Pesach Frank, too, addressed only the issue of wearing a hearing aid, apparently assuming that electricity was not an issue (Har Zvi, OC 173).
Rav Yaakov Breisch (Chelkat Yaakov vol. 3, 186) also dealt with the question of the difference between a microphone and a hearing aid. He opined that microphones may not be used on Shabbat because of the prohibitions of mashmi’a kol (creating a sound) and shema yetaken (lest one repair), neither of which applies to a hearing aid. Furthermore, he asked, “Is it conceivable that if someone – Jew or Gentile – came to synagogue or to one’s house while wearing a hearing aid, that no one would be permitted to utter a sound in his presence? I believe that no one would forbid such a thing, since (unlike a loudspeaker) one does not speak directly into a hearing aid, but rather one speaks as usual and the hearing aid picks up the sound of his speech.” It is clear that Rav Breisch is concerned only with the problems of mashmi’a kol and shema yetaken (which we shall discuss in chapter 2), but not with the issue of electricity.
Similarly, Rav Moshe Feinstein (Igrot Moshe, OC 4:85) permitted the use of hearing aids on Shabbat, distinguishing (in terms of mashmi’a kol) between a loudly amplified sound and the lower volume of a hearing aid. “Since it is not clear which melacha this resembles, we cannot forbid [the use of hearing aids] for ill people and for a great need … and the potential problem of utilizing electricity is not a clear prohibition, nor is it even a clear safek (doubt).”
Shemirat Shabbat K’hilchata (34:28) writes, “It is permissible for those who are hard of hearing to use an electric hearing aid on Shabbat, as long as it is turned on before Shabbat. Furthermore, it is permissible to adjust the volume on the hearing aid if no wires become red-hot.” He adds in the third volume (corrections and addenda), “Rav Shlomo Zalman Auerbach zt”l further stated that it is permissible to speak on Shabbat to a person wearing a hearing aid, for despite the fact that his speech affects the current in the hearing aid, nevertheless the change is miniscule even at the moment of his speech, such that even the Chazon Ish zt”l would not consider it boneh or soter (building or taking apart). However, the Chazon Ish’s opinion on the permissibility of a device where the changes occur in the wire carrying the current [i.e. where the wire reddens or brightens – Y.R.] is not clear to me.”
In other words, contemporary halachic authorities permit the use of hearing aids on Shabbat, and do not see any prohibition of electricity involved.
Comment: On the Hearing Aid rulingWhen You read what the rabbis had to say about the subject of the usage of all types of Microphone technologies on Shabbat in the article cited above https://www.zomet.org.il/eng/?CategoryID=198&ArticleID=283#b5 you might be surprised to find out that most rabbis found reasons to ban them.
True, there might be very slight differences between hearing aids and microphones, to allow for the first but ban the second. For example, the intensity of the sound produced by hearing aids vs. microphones, or the greater likelihood that people would abuse a leniency for microphones to violate Shabbat.
But I think there is a deeper issue behind the leniency on hearing aids.
In the case of hearing aids, the Poskim, (The leading Halachic authorities, that rule on Jewish law) are convinced there is a real “need” for this technology and the overall outcome of this technology will be an improvement in health and even Shabbat observance in general.
A majority of the Poskim currently believe this is not the case for microphone technology.