2 Kings 2:19-22

19And the men of the city said to Elisha, Behold now, the situation of the city is good, as my lord sees; but the water is bad, and the land is barren.

20And he said, Bring me a new cruse, and put salt in it. And they brought it to him.

21And he went forth to the source of the waters, and cast the salt in there, and said, Thus saith Jehovah: I have healed these waters: there shall not be from thence any more death or barrenness.

22And the waters were healed to this day, according to the saying of Elisha which he spoke.