Deuteronomy 32:45-47

And Moses made an end of speaking all these words to all Israel; and he said unto them, Set your heart unto all the words which I testify unto you this day, which ye shall command your children to observe to do, even all the words of this law. For it is no vain thing for you; because it is your life, and through this thing ye shall prolong your days in the land, whither ye go over the Jordan to possess it.