Our Sages teach us in the Gemara in Masechet Avodah Zarah (28b): “A man’s eyes are connected to his heart.” Thus, if we see that one’s eye is in danger, it is tantamount to revealing an ailment in the person’s heart and we must certainly rush to desecrate Shabbat in order to prevent his death.
Based on this, if one experiences eye pain on Shabbat and they emit certain discharges, such as puss and the like, or if one has a serious infection in one’s eye, one is considered to be ill with a life-threatening illness; based on what we have explained in previous Halachot, Shabbat must be desecrated on his behalf through rubbing some creams on his eye, boiling water for him, driving him to the doctor so he can seek treatment, and the like.
Nevertheless, according to modern medicine, no connection exists between the eyes and the heart and even if one were to incur a massive illness in one’s eye, this has no impact on the health of one’s heart. There is no reason to think that one may die from such an ailment; the worst case scenario is that the condition may cause blindness.
It is quoted in the works of the Rishonim that a certain maidservant’s (Mor Shmuel’s maid) eye was stricken on Shabbat and although she complained about the pain profusely, no one bothered to resolve the issue on Shabbat itself. The next day, Sunday, this maidservant died. After an autopsy was performed on her, it was determined that certain cords from her eye were connected to her heart and her eye ailment was indeed her cause of death.
Modern medicine rejects these views completely as we have already established and we must inevitably explain that human nature has changed regarding this matter as we find regarding many other matters that, without a doubt, many things were different than they are nowadays; we must therefore conclude that the reality of human nature has since changed in these aspects. It is well-known that in a matter of a few decades, many significant changes in the nature of humanity can occur. Thus, based on this, nowadays, one may not desecrate Shabbat for one suffering from eye pain.
Maran zt”l deals with this matter extensively and writes that some say that one should never accept the opinions of modern medicine and doctors against the tradition of our Sages who knew quite well that there is a correlation between the eyes and the heart and that an eye ailment may very well lead to death. The Poskim discuss this matter especially with regards to circumcising a child who is suffering from eye inflammation, for according to our Sages, the child should not have his Berit Milah until he recuperates, whereas according to doctors, there is really nothing to worry about. We rule in accordance with the opinion of our Sages and the child is not circumcised until he heals. Hagaon Harav Avraham Yitzchak HaKohen Kook rules accordingly in his Sefer Da’at Kohen where he writes that not only must the baby recuperate before the Milah is performed, but an additional seven days after the baby recovers must be likewise pass before the Milah is performed. Although Hagaon Harav Yosef Shalom Elyashiv zt”l is of the opinion that nowadays, Shabbat should not be desecrated on behalf of someone suffering from an eye ailment based on what modern-day doctors have said that this does not pose a danger to one’s life, nevertheless, when combining the opinion of some doctors even nowadays who say that such eye ailments do indeed pose life-threatening situations with the edict of our Sages, it seems that even nowadays, one may desecrate the Shabbat on behalf of someone suffering from an eye ailment.
Thus, halachically speaking, let us quote the words of Hagaon Harav Shlomo Zalman Auerbach zt”l: “When one experiences a sharp and strong eye inflammation, sharp eye pains, an eye injury, or a severe loss of vision, Shabbat should be desecrated.” All this applies even if these symptoms occur only in one eye.
Similarly, if one sustains an eye injury on Shabbat and the retina of one eye becomes torn, he should be instructed to immediately drive to the hospital to save the eye from blindness. Similarly, one may rub creams on the eye on Shabbat or soak a towel with some hot water and other ingredients and place it on the eye on Shabbat; one should just take care not to squeeze the towel while doing so.
One may also act leniently and use eye-drops on Shabbat if one is unsure whether or not one has an eye infection since using eye-drops on Shabbat does not entail a Torah prohibition.
Summary: If someone suffers from extreme eye inflammation, severe loss of vision, severe eye pain, or if one experiences pain similar to a poking sensation in one’s eyes and the like on Shabbat, even if it is only in one eye, one should desecrate Shabbat on his behalf in order to transport him to the hospital or anything else that is necessary to heal him. Additionally, one may use eye-drops on Shabbat for an eye infection, even if one is unsure whether or not one has indeed has contracted such an infection.