Deuteronomy 11:21 in the King James Version
That your days may be multiplied, and the days of your children, in the land which the LORD sware unto your fathers to give them, as the days of heaven upon the earth.
Context
20 You shall write them on the door posts of your house and on your gates;
21 that your days and your children’s days may be multiplied in the land which the LORD swore to your fathers to give them, as the days of the heavens above the earth.
22 For if you shall diligently keep all these commandments which I command you—to do them, to love the LORD your God, to walk in all his ways, and to cling to him—