Gen 15:18 "On the same day the LORD made a covenant with Abram, saying: "To your descendants I have given this land, from the river of Egypt to the great river, the River Euphrates"
The "Great River", The River Euphrates
The Euphrates River
The Euphrates river is "the river" and "the great river" of the Bible. it is named as one of the rivers of Eden. The root of the word "Euphrates" is "Pehrat" which means "to break forth and abound."
The Euphrates river is about 1780 miles long and is the largest river in Southwestern Asia, and was always considered by the Hebrews as the ideal northeastern boundary of Israel.
1 King 4:21 "So Solomon reigned over all kingdoms from the River to the land of the Philistines, as far as the border of Egypt. They brought tribute and served Solomon all the days of his life."
The Euphrates river overflows its banks, like the Nile, every year and rises as high as 12 feet during the months of March, April, and May because of the melting of the snows. People in ancient times often referred to cities dwelling on one side or the other side of the great river Euphrates. The Greeks used to say, "to cross the Euphrates was to cross the Rubicon." It was the western boundary of Mesopotamia, dividing it from the "Land of Hatti," which included all land between the Euphrates and the Mediterranean; Babylon bordered this river, as Nineveh did upon the Tigris River. It flowed by other ancient cities, such as Carchemish (2 Chr. 35:20) and Sippar, Agade, Borsippa, and Ur.
According to Xenophon, The Euphrates caused the desert to "become a garden of fertility."
The Book of Revelation and the River Euphrates
There are future events mentioned in the Book of Revelation concerning the Euphrates river:
Rev 9:14-16 14 saying to the sixth angel who had the trumpet, "Release the four angels who are bound at the great river Euphrates." 15 So the four angels, who had been prepared for the hour and day and month and year, were released to kill a third of mankind. 16 Now the number of the army of the horsemen was two hundred million; I heard the number of them.
Rev 16:12 "Then the sixth angel poured out his bowl on the great river Euphrates, and its water was dried up, so that the way of the kings from the east might be prepared."
Bibliography on Ancient Customs
The Art of Ancient Egypt, Revised by Robins, 272 Pages, Pub. 2008