In the same day the LORD made a covenant with Abram, saying,
Unto your descendants have I given this land, from the river of Egypt unto the great river, the river Euphrates:
All Commentaries on Genesis 15:18 Go To Genesis 15
George Leo Haydock
AD 1849
Of Egypt, a branch of the Nile, not far from Pelusium. This was to be the southern limit, and the Euphrates the northern; the two other boundaries are given, Numbers xxxiv.
Perhaps Solomon's empire extended so far. At least, the Jews would have enjoyed these territories, if they had been faithful. (Menochius)