Isaiah 43:19

Behold, I will do a new thing
A wonderful and unheard of thing, and therefore introduced with a "behold", as a note of admiration; the same with the new thing created in the earth, ( Jeremiah 31:22 ) , the incarnation of the Son of God; who took flesh of a virgin, appeared in the likeness of sinful flesh, and was made sin and a curse for his people, in order to obtain eternal redemption for them; which blessing, though not newly thought of, resolved on, contrived, and agreed upon, that being from eternity; nor newly made known, or as to the virtue and efficacy of it, which had been from the beginning of the world, yet new as to the impetration of it by the blood and sacrifice of Christ; and may be also called "new", because excellent, it being of a spiritual nature, complete and eternal, and having so many valuable blessings in it, as justification, pardon, and eternal life: now it shall spring forth;
or bud forth as a branch, in a very short time, suddenly, and at once; one of the Messiah's names is that of the Branch; see ( Zechariah 3:8 ) ( 6:12 ) : shall ye not know it?
the Redeemer, and the redemption by him. It was known to them that looked for it, and to whom the Gospel is sent, and the Spirit reveals and applies it; these know the nature of it, own it to be of God, and know their interest in it, and know the author of it, in whom they have believed, by the characters given of him: and as this may have respect to the redemption of Christ, so to the conversion of the Gentiles, and to the grace of God dispensed through Christ to them; when old things passed away, and all things became new; a new covenant of grace was exhibited, a new church state set up, new ordinances appointed, and a new people called to partake of all this, on whom was a new face of things; and wonderful and excellent things were done for them, as follows: I will even make a way in the wilderness;
as there was a way made for the Israelites through the wilderness, which lay between Egypt and Canaan; and through another, which lay between Babylon and Judea; so the Lord would also make a way in the Gentile world, comparable to a wilderness for its barrenness and unfruitfulness, for the Gospel to enter into it, where it should run, and be glorified; where Christ, the way of salvation, should be made known; and where there should be a way for Christians to walk together, in the fellowship of the Gospel: and rivers in the desert;
the doctrines of the Gospel, and the ordinances of it, which should be preached and administered in the Gentile world, before like a desert; and the graces of the Spirit, which should be brought into the hearts of men by means of them; and the large communications of grace from Christ; and the discoveries of the love of God, with the blessings of it; compared to rivers for their abundance, and for the comforting, reviving, and fructifying nature of them.