Deuteronomy 4:9-10

9 Only take heed to yourself, and keep your soul diligently, lest you forget the things which your eyes have seen, and lest they depart from your heart all the days of your life: but teach them your sons, and your sons' sons;

10 Specially the day that you stood before the LORD your God in Horeb, when the LORD said to me, Gather me the people together, and I will make them hear my words, that they may learn to fear me all the days that they shall live on the earth, and that they may teach their children.