This week's Torah portion tells the story of Isaac, who became blind at the end of his life. Our sages dwell on explaining the cause of Isaac's blindness, even though the verse clearly states (Genesis 27:1), "And it came to pass when Isaac grew old, that the sight of his eyes grew dim." Apparently, the Torah itself is informing us that the cause of Isaac's blindness is old age, as is common and normal even today. If this is the case, why does Rashi (a prominent commentator) offer three reasons for Isaac's blindness? Clearly, there is something special about his blindness, different from that of a simple old man. To explain, here are two stories:
It is said that Reb Nachum Chernobyl (1730-1798) entered a room one Friday night, already on Shabbat, and began feeling his way along the walls, trying to reach a specific place. Someone told him, "But there's a candle lit," to which he replied, "I don't see any candle lit..." After this incident, it was discovered that the candle in the room had been lit on Shabbat, transgressing the Torah. Reb Nachum, because of the refined and holy nature of his constitution, did not perceive the forbidden light of that candle.
Similarly, it is told about the fifth Rebbe of Chabad, Rabbi Shalom Dov Ber (1860-1920), that on one occasion, while giving a Hasidic discourse, he heard people conversing in an adjacent room and, as this bothered him, he ended up deafening the ear closest to that room...
The same thing happened to Isaac. Rashi explains, in his first commentary, that the incense offered to idolatry by the wives of Esau, Isaac's son, caused his blindness. Has anyone ever been blinded by incense smoke? It might be unpleasant, but to be blind... One way to understand it is that Isaac suppressed his physical sight so as not to see what was inappropriate.
Now, the very reason each story reaches our ears is so that we may derive something from it in our service to God. We are not at the spiritual level of Reb Nachum Chernobyl, Rebbe Shalom Dov Ber, or Isaac our patriarch to have such a profound effect on the body, but we certainly encounter situations daily on the street, in the office, and in various other environments that we should not see and words that we should not hear. The most basic lesson of the story of Isaac and his self-imposed blindness is that we must indeed close our eyes or look the other way when it is appropriate according to the Torah. And if someone were to ask, "How do I know what is appropriate?" Well, one should simply ask oneself: "Would Isaac see this?"