Is the river of Egypt in Genesis 15:18 the same as the Nile River?
No, it is not necessarily the Nile. The river of Egypt may have been a different river in antiquity, located a little east of the Nile, which was called the river of Egypt. Genesis 15:18 marks the land’s boundary from that river to the Euphrates.
Les teaches from Genesis 15:18 that God made a covenant with Abram and deeded the land from the river of Egypt to the great river Euphrates. He explains that he will not call the river of Egypt the Nile, because he thinks there was another river back in antiquity a little east of the Nile called the river of Egypt. He adds that everything between the Mediterranean Sea and the Euphrates was deeded to Abraham, and that since Desert Storm people are aware of where the Euphrates flows.
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: