The names conferred upon the brothers are pregnant with meaning. The older was called Esau, because he was 'Asui, fully developed when he was born, and the name of the younger was given to him by God, to point to some important events in the future of Israel by the numerical value of each letter. The first letter in Ya'akob, Yod, with the value of ten, stands for the decalogue; the second, 'Ayin, equal to seventy, for the seventy elders, the leaders of Israel; the third, Kof, a hundred, for the Temple, a hundred ells in height; and the last, Bet, for the two tables of stone.