Yes, because I read the passages that they cited.
You see the limits of Solomons kingdom in 1Ki.4:21 (cf 2Chron.9:26) where it states that Solomon ruled a kingdom which went to the border of Egypt not into it (the Nile).
Gen.15:8 is speaking of going from the river of Egypt (the Nile) to the Euphrates.
The Nile was the border of Egypt in those days. It served as the boundary and guard for Egypt's eastern border.