And the name of the third river is Tigris: the same passeth along by the Assyrians. And the fourth river is Euphrates.
Rashi
חדקל TIGRIS — It is called חדקל because its waters are pungent in taste (חד) and light in weight (קל) (Berakhot 59b). פרת EUPHRATES — It is called פרת because its waters grow (פרה) and increase and make men healthy (Berakhot 59b). כוש ואשור CUSH AND ASHUR did not then exist as countries, but Scripture writes with reference to the names which those districts would bear in the future (Ketubot 10b; Genesis Rabbah 16). קדמת אשור means AT THE EAST OF ASHUR. הוא פרת IS THE EUPHRATES — the most important of all, being mentioned in connection with the Land of Israel (Genesis Rabbah 16:3).
Hebrew and Aramaic words are the commentator’s citations of the sacred text; the English translation that follows each is the translator’s.
Imported from an open dataset — not yet checked against the printed edition.