Jacob was thus the only one among Joseph's closest kinsmen that remained in ignorance of his son's real fortunes, and he was the one of them all that had the greatest reason for regretting his death. He spoke: "The covenant that God made with me regarding the twelve tribes is null and void now. I did strive in vain to establish the twelve tribes, seeing that now the death of Joseph hath destroyed the covenant. All the works of God were made to correspond to the number of the tribes—twelve are the signs of the zodiac, twelve the months, twelve hours hath the day, twelve the night, and twelve stones are set in Aaron's breastplate—and now that Joseph hath departed, the covenant of the tribes is set at naught." He could not replace the lost son by entering into a new marriage, for he had made the promise to his father-in-law to take none beside his daughters to wife, and this promise, as he interpreted it, held good after the death of Laban's daughters as well as while they were alive.[70] Beside grief over his loss and regret at the breaking of the covenant of the tribes, Jacob had still another reason for mourning the death of Joseph. God had said to Jacob, "If none of thy sons dies during thy lifetime, thou mayest look upon it as a token that thou wilt not be put in Gehenna after thy death." Thinking Joseph to be dead, Jacob had his own fate to bewail, too, for he now believed that he was doomed to Gehenna.[71] His mourning lasted all of twenty-two years, corresponding to the number of the years he had dwelt apart from his parents, and had not fulfilled the duty of a son toward them.[72] In his mourning Jacob put sackcloth upon his loins, and therein be became a model for the kings and princes in Israel, for David, Ahab, Joram, and Mordecai did likewise when a great misfortune befell the nation.[73] JUDAH AND HIS SONS When the sons of Jacob saw how inconsolable their father was, they went to Judah, and said to him, "This great misfortune is thy fault." Judah replied: "It was I that asked you, What profit is it if we slay our brother and conceal his blood? and now you say the sin lies at my door." The brethren continued to argue: "But it was thou that didst say, Come and let us sell him to the Ishmaelites, and we followed thy advice. Hadst thou said, Let us restore him to his father, we had heeded these words of thine as well."