Gen 2:14

“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).”

“The name of the third river is Hiddekel,.... A river which ran by Shushan in Persia, and retained its name in the times of Daniel, Dan 10:4 where it is called the great river; and it seems it bears the same name now among the Persians; at least it did an hundred and fifty years ago, when Rauwolff (m) travelled in those parts. The Targum of Jonathan here calls it Diglath, the same with the Diglito of Pliny (n); and according to him it is called Tigris, from its swiftness, either from the tiger, a swift creature, or from "to dart", in the Chaldee language; and so Curtius (o) says, that in the Persian language they call a dart "tigris": and with this agrees the word "Hiddekel", which in the Hebrew language signifies sharp and swift, as a polished arrow is; and Jarchi says it is so called, because its waters are sharp and swift: though this is contradicted by some modern travellers (p) who say it is a slower stream than the Euphrates, and is not only very crooked, and full of meanders, but also choked up with islands, and great banks of stone: that is it which goeth towards the east of Assyria: a country which had its name from Ashur, a son of Shem, Gen 10:11 it became a famous kingdom and monarchy, Nineveh was the metropolis of it, which was built on the river Tigris or Hiddekel; and, as before observed, it ran by Shushan in Persia; and so, as Diodorus Siculus (q) says, it passed through Media into Mesopotamia; and which very well agrees with its being, according to Moses, one of the rivers of Eden. Twelve miles up this river, from Mosul, near which Nineveh once stood, lies an island, called the island of Eden, in the heart of the Tigris, about ten English miles in circuit, and is said to be undoubtedly a part of paradise (r): and the fourth river is Euphrates: or "Phrat", as in the Hebrew tongue. Reland (s) seems rightly to judge, that the syllable "eu", prefixed to it, is the Persian "au" or "cu", which in that language signifies "water"; so that "Euphrates" is no other than "the water of Phrat", so called from the fruitfulness of it; for its waters, as Jarchi says, fructify, increase, and fatten the earth; and who rightly observes that these names, and so those of other rivers, and of the countries here mentioned, are named by a prolepsis or anticipation, these being the names they bore when Moses wrote; unless it may be thought to be the Hebrew "Hu, the, that Phrat"; and which the Greeks have made an "eu" of. (After the global destruction of Noah's flood, it is doubtful that the location of these rivers could be determined with any degree of certainty today. Ed.) (m) Travels, part. 2. c. 9. p. 159. ed. Ray. (n) Nat. Hist. l. 6. c. 27. (o) Hist. l. 4. c. 9. (p) De la Valle & Thevenot, apud Universal History, vol. 4. p. 248. (q) Bibliothec. l. 2. p. 99. (r) Cartwright's Preacher's Travels, p. 91. (s) Ut supra, (De Situ Paradisi) p. 45.”