Unto thy seed have I given this land, from the river of Egypt, &c. In David's time and Solomon's, their jurisdiction extended to the utmost of those limits, 2 Chronicles 9:26. And it was their own fault that they were not sooner and longer in possession of all these territories. They forfeited their right by their sins, and by their own sloth and cowardice kept themselves out of possession.
Related Commentaries of Genesis 15:18
Genesis 15:18
18 In the same day the LORD made a covenant with Abram, saying, Unto thy seed have I given this land, from the river of Egypt unto the great river, the river Euphrates: