Isaiah 41:18

I will open rivers in high places, and fountains in the midst of the valleys: I will make the wilderness a pool of water, and the dry land springs of water.

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 passed over; this is in high places, it flows from the throne of God, and of the Lamb; and of this river of pleasure he makes his people to drink, the streams whereof make glad the city of our God; likewise the fulness of grace in his Son, whose grace is as rivers of water in a dry land, exceeding abundant, and very refreshing; also the graces of his Spirit, which he gives in great abundance, and are those rivers of water he causes to flow forth from them that believe in Christ, in the comfortable exercise of them; see

Psalms 36:8,

and fountains in the midst of the valleys; God himself is the fountain of life, and of living waters; Christ is the fountain of gardens, and in him are wells of salvation; the grace of the Spirit is a well of living water, springing up unto eternal life; and of these, humble souls, comparable to the lowly valleys, are partakers,

Psalms 36:9:

I will make the wilderness a pool of water, and the dry land springs of water; respecting either the Gentile world, which was like a wilderness and dry land before the Gospel came into it, but by that was watered and made fruitful; or the state and case of the people of God being in a wilderness condition, when the Lord takes notice of them, and supplies them with everything necessary, so that they are like a watered garden, whose springs fail not, Revelation 12:14. This passage is applied by the Jews to the times of the Messiah {w}.

{w} Bemidbar Rabba, sect. 1. 4. fol. 212. 3.