Why Jacob Warned His Sons Against the Evil Eye in Egypt

"And Jacob said to his sons, Why do you make yourselves conspicuous?" (Genesis 42:1). Jacob said to them: I beg of you, conceal yourselves, for there is nothing more harmful than the evil eye. And so you find with the first tablets: because they were given amid greatness, they were shattered, as it is said, "And all the people saw the thunderings" (Exodus 20:18). But the second tablets, when they were given, no one saw them except Moses, as it is said, "And no man shall come up with you" (Exodus 34:3). And Jerusalem too was destroyed only on account of an evil eye, as it is said, "Is this the city that they called the perfection of beauty, the joy of all the earth?" (Lamentations 2:15), and it says, "My eye affects my soul because of all the daughters of my city" (Lamentations 3:51). Therefore Jacob said: Do not make yourselves seen, as it is said, "And Jacob said to his sons, Why do you make yourselves conspicuous?" Rather walk in concealment, as it is said, "He has told you, O man, what is good... and to walk humbly with your God" (Micah 6:8).