And we divided the Israelites into twelve tribes, as nations; and we revealed unto Moses when the people asked drink of him - "Strike the rock with thy staff:" and there gushed forth from it twelve fountains - the men all knew their drinking places. And we caused clouds to overshadow them, and sent down upon them the manna and the quails. . . . "Eat of the good things with which we have supplied you." But it was not us whom they injured, but they injured their own selves: