Deuteronomy 11:16-21

Beware that your hearts are not deceived, and that you do not turn away and serve other gods and worship them. Or the anger of the LORD will be kindled against you, and He will shut up the heavens so that there will be no rain and the ground will not yield its fruit; and you will perish quickly from the good land which the LORD is giving you. “You shall therefore impress these words of mine on your heart and on your soul; and you shall bind them as a sign on your hand, and they shall be as frontals on your forehead. You shall teach them to your sons, talking of them when you sit in your house and when you walk along the road and when you lie down and when you rise up. You shall write them on the doorposts of your house and on your gates, so that your days and the days of your sons may be multiplied on the land which the LORD swore to your fathers to give them, as long as the heavens remain above the earth.