I will make waste mountains... — The whole description is symbolic, and points to the subjugation of the heathen nations, the “rivers” and “pools” probably representing the kingdoms of the Tigris and Euphrates (Isaiah 8:7). All this seems a purely destructive work, but through it all mercy and truth are working, and a way is being opened for the return of Israel, in painting which, as elsewhere, the literal melts into the spiritual, as in a dissolving view. (See Note on Isaiah 40:4.) “These things” include the whole work of judgment and of mercy.
Related Commentaries of Isaiah 42:15
Isaiah 42:15
15 I will make waste mountains and hills, and dry up all their herbs; and I will make the rivers islands, and I will dry up the pools.