Genesis 26:1-6; 1 Peter 2:9-10

1 Now there was a famine in the land, besides the former famine that had occurred in the days of Abraham. And Isaac went to Gerar, to King Abimelech of the Philistines. 2 The Lord appeared to Isaac and said, "Do not go down to Egypt; settle in the land that I shall show you. 3 Reside in this land as an alien, and I will be with you, and will bless you; for to you and to your descendants I will give all these lands, and I will fulfill the oath that I swore to your father Abraham. 4 I will make your offspring as numerous as the stars of heaven, and will give to your offspring all these lands; and all the nations of the earth shall gain blessing for themselves through your offspring, 5 because Abraham obeyed my voice and kept my charge, my commandments, my statutes, and my laws." 6 So Isaac settled in Gerar.
9 But you are a chosen race, a royal priesthood, a holy nation, God's own people, in order that you may proclaim the mighty acts of him who called you out of darkness into his marvelous light. 10 Once you were not a people, but now you are God's people; once you had not received mercy, but now you have received mercy.