Deuteronomy 10:16-21

So circumcise [that is, remove sin from] your heart, and be stiff-necked (stubborn, obstinate) no longer. For the LORD your God is the God of gods and the Lord of lords, the great, the mighty, the awesome God who does not show partiality nor take a bribe. He executes justice for the orphan and the widow, and shows His love for the stranger (resident alien, foreigner) by giving him food and clothing. Therefore, show your love for the stranger, for you were strangers in the land of Egypt. You shall fear [and worship] the LORD your God [with awe-filled reverence and profound respect]; you shall serve Him and cling to Him [hold tightly to Him, be united with Him], and you shall swear [oaths] by His name. He is your praise and glory; He is your God, who has done for you these great and awesome things which you have seen with your own eyes.