At the same time he had brought the scourge of blindness down upon himself by his love for Esau. He justified the wicked for a bribe, the bribe of Esau's filial love, and loss of vision is the punishment that follows the taking of bribes. "A gift," it is said, "blinds the eyes of the wise."
Nevertheless his blindness proved a benefit for Isaac as well as Jacob. In consequence of his physical ailments, Isaac had to keep at home, and so he was spared the pain of being pointed out by the people as the father of the wicked Esau. And, again, if his power of vision had been unimpaired, he would not have blessed Jacob. As it was, God treated him as a physician treats a sick man who is forbidden to drink wine, for which, however, he has a strong desire. To placate him, the physician orders that warm water be given him in the dark, and he be told that it is wine.