But its swamps and marshes will not become fresh: The pronoun its refers to the Dead Sea, not the river. Swamps are large areas of shallow water that are not deep enough to fish in. With their large surface area, they tend to evaporate quickly, leaving salty residue on the ground. The Hebrew word for swamps is used only here and in Job 8.11 and 40.21. Marshes are muddy pools or holes filled with water (compare Isa 30.14, where the Hebrew word for marshes is rendered “cistern”). It is not necessary to distinguish between swamps and marshes; for example, New International Reader’s Version renders this clause as “But none of the swamps will have fresh water in them,” and Contemporary English Version has “But the marshes along the shore will remain salty.” Become fresh is literally “be healed” (King James Version; see Ezek 47.8).
They are to be left for salt: The Hebrew expression here may mean the marshy areas “will remain salty” (Contemporary English Version) or they “will be places to get salt.” Salt was an important commodity in the ancient world as a preservative for food. The Dead Sea area was the source of much of ancient Israel’s salt, so Ezekiel foresees that the miraculous water flowing out of the Temple will not freshen all the water, because that would remove this important source of salt.
Quoted with permission from Gross, Carl & Stine, Philip C. A Handbook on Ezekiel. (UBS Helps for Translators). Miami: UBS, 2016. For this and other handbooks for translators see here .

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