I will open rivers on the bare heights, and fountains in the midst of the valleys. I will make the wilderness a pool of water, and the dry land springs of water.
18. and 19. I will open rivers. He illustrates the former doctrine in a different manner, namely, that God has no need of outward and natural means for aiding his Church, but has at his command secret, and wonderful methods, by which he can relieve their necessities, contrary to all hope and outward appearance.
The scope of these verses is to silence the fears, and encourage the faith, of the servants of God in their distresses. Perhaps it is intended, in the first place, for the support of God's Israel, in captivity; but all that faithfully serve God through patience and comfort of this scripture may have hope.
Commenting on Isaiah 41:10-20
I will open rivers in high places,.... Which is not usual; but God will change the course of nature, and work miracles, rather than his people shall want what is necessary for them; thus he opens to them his everlasting and unchangeable love, and makes it manifest, and shows it to them, and their interest in it, which is a broad river, that cannot be...