Problem: God promised Abraham, “To your descendants I have given this land, from the river of Egypt to the great … River Euphrates” (Gen. 15:18; cf. Deut. 11:24). However, when Joshua divided the land Israel inherited, the boundaries listed do not mention the Euphrates, but cities to the west of it (Josh. 13:9–12).
Solution: Joshua is simply dividing up the land that was taken by the Israelites, not everything that was given to them. Even though Joshua’s forces conquered the land as a whole (cf. Josh. 11:23), they obviously did not occupy all the land in particular (cf. Jud. 1:27–36). Much later in David’s day they were still extending their border toward the Euphrates (2 Sam. 8:3). This reveals that they understood the repeated promise (cf. Gen. 15:18; Deut. 1:7; 11:24) to include land up to the Euphrates as their eastern border. Indeed, even Joshua mentions this same border when he repeats the pomise to Israel (Josh. 1:4).
