And it came to pass, when Yitzchak had become old and his eyes dimmed from seeing… (Bereishis 27:1)
There is broad and extensive Halachic discussion of blindness. One of the important topics is the permissibility of Chilul Shabbos in order to prevent someone from losing his sight. In this essay, we will discuss a number of the considerations of the Poskim.
Chaza”l considered diseases of the eyes and eye injuries extremely serious. The Gemara in Avoda Zara 28b discusses this in some detail:
R’ Zutra bar Tuvia said in the name of Rav: One may apply ointment to an “Ayin sheMarda” on Shabbos. [Those in attendance] thought that this is only true if the herbs [from which the ointment is prepared] were already crushed on the previous day [and therefore there would only be an Issur d’Rabbanan of Refua], but to crush them on Shabbos or to carry them [to bring them to the patient] through a Reshus haRabim [which are Issurim d’Oraisa] would not be permissible. [The reason they thought this was that the person was only in danger of losing his eyesight, not his life – Rashi].
One of the Rabbis, R’ Yaakov was his name, said to them – The ruling of R’ Yehuda was explained to me: It is even permissible to crush the herbs on Shabbos or carry them in a Reshus haRabim [as it is considered a matter of Pikuach Nefesh].
The Gemara elaborates further:
R’ Yehuda permitted application of ointment to an eye on Shabbos. R’ Shmuel bar Yehuda said, “Who will listen to Yehuda who desecrates Shabbos?” Ultimately R’ Shmuel contracted a disease in his eye. He sent a question to R’ Yehuda: “Is it permissible or forbidden [to apply an ointment to my eye on Shabbos]?” He responded: “For everybody else it is permissible but for you [who rejected my lenient ruling] it is forbidden. Did you think that the ruling was my own? I received it from Mar Shmuel [who gave this ruling in the following context:]
There was a maidservant in the household of Mar Shmuel, whose eye became infected on Shabbos. She cried but nobody paid any attention to her [as they didn’t think there was any danger to her eye]. Her eye popped out [of its socket]. The following day, Mar Shmuel went out and taught: “Ayin sheMarda” – one may apply ointment to it on Shabbos. Why? “Sheshurayna d’Eina b’Uvnesa d’Liba Talu” [see below].
What examples are there [of eye ailments that are considered life-threatening]? Said R’ Yehuda: For instance; “Rira” (abnormal discharge), “Ditza” (a painful sensation indicative of inflammation), bleeding or excessive tearing [due to the pain], or “Kidcha” (a burning or stinging sensation, probably caused by infection). [One may only desecrate Shabbos to treat these conditions] at the onset of the ailment, but not when the ailment is practically finished, and not merely to improve one’s eyesight.
The Gemara explains that certain ailments of the eyes are a matter of Pikuach Nefesh because “Shurayna d’Eina b’Uvnesa d’Liba Talu”. Rashi (s.v. Afilu) explains: “The eyesight is connected and linked to the membranes (alternatively, valves) of the heart”, thus a disease of the eye endangers the heart which is a definite Sakana.
Tosfos offer a different explanation. They say that the meaning of “Shurayna d’Eina b’Uvnesa d’Liba Talu” is, “vision depends upon the understanding of the heart”, implying that a disease of the eyes does not pose a danger to the rest of the body, just to the eyes themselves. The same position is taken by Tosfos in Maseches Sukah (26a). The Gemara there rules that if a person has an eye ailment he is exempt from the Mitzva of Sukah. Tosfos (in the name of Rabbenu Tam) explain, that although the ailment does not pose a danger to life, nevertheless, the Gemara in Avoda Zara rules that a danger to one limb of the body is considered Sakanas Nefashos.
The Shulchan Aruch (O.C. 328:9) rules:
If a person has an ailment in both of his eyes, or in one of them, and there is discharge, tearing from pain, bleeding, or pus, and it is the onset of the ailment, one may desecrate Shabbos.
As stated, according to Rashi, the eye ailments referenced pose an actual danger to life and not merely to eyesight. In fact, originally when the Gemara assumed that the danger was merely to eyesight, it did not permit Chilul Shabbos in order to treat it. (This is also the Ramban’s understanding of Rashi.)
Even Tosfos who hold that the danger is limited to the eyes, do not consider eye ailments to be more dangerous than diseases which affect other limbs of the body. Rabbenu Tam holds that anything that endangers a limb of the body (“Sakanas Eiver”) is considered a Sakana, and therefore we are permitted to be Mechalel Shabbos to treat certain ophthalmic conditions. In fact, the risk of blindness alone would not justify Chilul Shabbos (e.g. in a theoretical case where there was no Sakanas Eiver to the eyes themselves).
This was also the conclusion of Rav Ovadia Yosef zt”l (Yabia Omer 3, Y.D. 23) and Rav Shmuel Wosner zt”l (Shevet haLevi 8:94). Consequently, a danger to eyesight is not considered to be Sakanas Nefashos for which one may desecrate Shabbos (except according to Rabbenu Tam who holds that one may do so for Sakanas Eiver which is not the position of the Shulchan Aruch ibid. 17). However, a disease of the eye, which does pose a danger to life, is a justification for Chilul Shabbos (Shulchan Aruch ibid. 9).
Nevertheless, some Poskim argue that there is another reason to consider a loss of eyesight to be a matter of Pikuach Nefesh. The Maharam m’Rothenberg (Shu”t Maharam Prague 160) rules that one may desecrate Shabbos in order to cure a “Nichpeh” (epileptic) as he is constantly in danger of a seizure that might lead to falling into water or fire. (The Taz, Y.D. 84:24 and Chasam Sofer 76 similarly permit violating other Issurim to cure a Nichpeh). The same should apply to saving a person’s eyesight. Since a blind person is also in danger of falling on the stairs or being struck by vehicles (and he cannot be expected to remain in his house at all times), it should be permissible to desecrate Shabbos in order to save a person from blindness (Shevet m’Yehuda p314).
Rav Ovadia Yosef zt”l (Yabia Omer ibid.) cites this ruling but maintains that the Rishonim in Avoda Zara imply that the danger of going blind is not a matter of Pikuach Nefesh. Moreover, there is a basic difference between a Nichpeh, who is not in control of his actions during a seizure and isn’t a Bar Da’as and is therefore in grave danger of accidents, and a blind person who is absolutely a Bar Da’as and can take steps to protect himself.
Rav Shlomo Kluger zt”l (Chochmas Shlomo on Shulchan Aruch, O.C. 328:46) suggests another reason to permit Chilul Shabbos to save a person from going blind. He discusses a case of a person who was stricken with a disease of the eyes known as “Sanverim” or “Shvartze Shtor” and for whom doctors had despaired of finding a cure. There was one gentile hospital which could treat him, and which could potentially save him from losing his eyesight completely which would allow him to still go about unattended. However, the administration of the hospital insisted that their patients eat the non-Kosher food that they provided. The question was whether it was permissible for him to undergo treatment there.
He notes that the Gemara in Avoda Zara implies that potential blindness (which does not stem from a disease of the eyes) is nothing more than a Sakanas Eiver which, according to the Shulchan Aruch, is not a justification for Chilul Shabbos. However this is only true of potential blindness in one eye, which, even in the worst-case scenario, would leave a person with the ability to see with his other eye. If there is potential for blindness in both a person’s eyes, the Chochmas Shlomo argued that one should be able to desecrate Shabbos to cure him.
Rav Kluger zt”l reasoned that the usual source of the rule that one may desecrate Shabbos on account of Pikuach Nefesh is the Pasuk of “va’Chai Bahem”. However, the Gemara in Yoma (85b) cites another source for this Halacha which is the Pasuk of “v’Shamru B’nei Yisrael Es haShabbos”. R’ Yishmael explains that this Pasuk teaches us that “the Torah says that we should desecrate one Shabbos on his behalf so that he may observe many Shabbosos [in the future]” (“Chalel Alav Shabbos Achas”).
The majority of the Poskim hold that Halacha also reckons with R’ Yishmael’s source. Therefore, in cases where va’Chai Bahem does not apply, there is still a basis for overriding the Mitzvos due to “Chalel Alav Shabbos Achas”. For example, if a fetus is in danger, though one could not justify Chilul Shabbos to save its life on the basis of va’Chai Bahem (as a fetus is not considered a “Nefesh”), one may desecrate Shabbos due to the rule of Chalel Alav Shabbos Achas, since the fetus will ultimately be born and observe Shabbosos in the future.
This idea could serve as the basis for Chilul Shabbos to save a person from blindness. Since, according to R’ Yehuda (Bava Kama 87a), a blind person is exempt from Mitzva observance, it should be permissible to desecrate Shabbos to save a person’s eyesight so that he will be able to continue to observe the Mitzvos (Chalel Alav Shabbos Achas). Though the majority of the Poskim do not rule like R’ Yehuda in this matter (see the Beis Yosef O.C. 473), we must nevertheless be concerned for the minority opinion (namely Rabbenu Yerucham Nesiv 5:4) that the Halacha follows R’ Yehuda, as in matters of Pikuach Nefesh we do not follow the majority.
The Chochmas Shlomo adds that one could also make a case for desecrating Shabbos even if we completely dismiss Rabbenu Yerucham’s position. One who is blind will have greater obstacles to Talmud Torah than a sighted person, and the Gemara (Kiddushin 40b) states that learning Torah is greater than Mitzva performance. If Chaza”l permitted Chilul Shabbos to enable a person to observe more Mitzvos, they would certainly permit it so that he may learn Torah.
The Tzitz Eliezer (8:15:10) was astounded by the ruling of the Chochmas Shlomo. Firstly, the notion that one does not follow the majority in matters of Pikuach Nefesh is only applicable where there is a definite, small chance of danger. In that case, we must ignore the overwhelming probability that there is no danger, and desecrate Shabbos. However, in this case, according to the majority of the Poskim (who constitute the Halacha) there is no aspect of Pikuach Nefesh here at all.
Secondly, the principle of “Chalel Alav Shabbos Achas” was said of cases where if one doesn’t intervene, the person will die and be unable to fulfill Mitzvos in the future. How can one compare that to a case where the person will not be in physical danger but will merely be exempt Halachically from Mitzva performance?
Rav Waldenberg zt”l nevertheless concludes that one may be Mechalel Shabbos in order to save a person from blindness.
 Literally, “an eye that rebelled”. Rashi (ibid.) implies that this refers to exophthalmos; other explanations include inflammation with discharge of pus. See Encyclopedia Hilchatit Refuit, vol. 6, p. 131.
 In other words, the principle of “Shurayna d’Eina” is not the reason why Chaza”l allowed Chilul Shabbos for an “Ayin sheMarda”.
 However, treatment that is only intended to improve eyesight is forbidden on Shabbos (Mishna Berura 328:24). This is based upon Rashi’s explanation of the Gemara in Avoda Zara.
 Rav Isser Yehuda Unterman zt”l (1886-1976) was the Chief Rabbi of Tel Aviv from 1946-1964, and Ashkenazi Chief Rabbi of Israel from 1964-1972.
 Rav Kluger concludes that he wasn’t entirely certain that he could rely on this reasoning. Therefore, he only permitted Issurei d’Rabbanan or less than a Shiur.
 See also Tzitz Eliezer 14:84.