I. In general, it is a great and surprising change that is here foretold, v. 17. Lebanon, that was a forest, shall be turned into a fruitful field; and Carmel, that was a fruitful field, shall become a forest. It is a counterchange. Note, Great changes, both for the better and for the worse, are often made in a very little while. It was a sign given them of the defeat of Sennacherib that the ground should be more than ordinarily fruitful (ch. xxxvii. 30): You shall eat this year such as grows of itself; food for man shall be (as food for beasts is) the spontaneous product of the soil. Then Lebanon became a fruitful field, so fruitful that that which used to be reckoned a fruitful field in comparison with it was looked upon but as a forest. When a great harvest of souls was gathered in to Christ from among the Gentiles then the wilderness was turned into a fruitful field; and the Jewish church, that had long been a fruitful field, became a desolate and deserted forest, ch. liv. 1.