for all the land which you see I give to you and your descendants forever.
Genesis 13:15
Surrounding context
13:14 And the LORD said to Abram, after Lot had separated from him: "Lift your eyes now and look from the place where you are--northward, southward, eastward, and westward;
13:15 for all the land which you see I give to you and your descendants forever.
13:16 And I will make your descendants as the dust of the earth; so that if a man could number the dust of the earth, then your descendants also could be numbered.