It comes all to one whether we make these verses (as some do) the song itself that is to be sung by the Gentile world or a prophecy of what God will do to make way for the singing of that song, that evangelical new song.

I.He will appear in his power and glory more than ever. So he did in the preaching of his gospel, in the divine power and energy which went along with it, and in the wonderful success it had in the pulling down of Satan's stronghold, Isa 42:13, Isa 42:14. He had long held his peace, and been still, and refrained himself, while he winked at the times of the ignorance of the Gentile world (Act 17:30), and suffered all nations to walk in their own ways (Act 14:16); but now he shall go forth as a mighty man, as a man of war, to attack the devil's kingdom and give it a fatal blow. The going forth of the gospel is thus represented, Rev 6:2. Christ, in it, went forth conquering and to conquer. The ministry of the apostles is called their warfare; and they were the soldiers of Jesus Christ. He shall stir up jealousy, shall appear more jealous than ever for the glory of his own name and against idolatry. 1. He shall cry, in the preaching of his word, cry like a travailing woman; for the ministers of Christ preached as men in earnest, and that travailed in birth again till they saw Christ formed in the souls of the people, Gal 4:19. He shall cry, yea, roar, in the gospel woes, which are more terrible than the roaring of a lion, and which must be preached along with gospel blessings to awaken a sleeping world. 2. He shall conquer by the power of his Spirit: He shall prevail against his enemies, shall prevail to make them friends, Col 1:21. Those that contradict and blaspheme his gospel, he shall prevail to put them to silence and shame. He will destroy and devour at once all the oppositions of the powers of darkness. Satan shall fall as lightning from heaven, and he that had the power of death shall be destroyed. As a type and figure of this, to make way for the redemption of the Jews out of Babylon, God will humble the pride, and break the power, of their oppressors, and will at once destroy and devour the Babylonian monarchy. In accomplishing this destruction of Babylon by the Persian army under the command of Cyrus, he will make waste mountains and hills, level the country, and dry up all their herbs. The army, as usual, shall either carry off the forage or destroy it, and by laying bridges of boats over rivers shall turn them into islands, and so drain the fens and low grounds, to make way for the march of their army, that the pools shall be dried up. Thus, when the gospel shall be preached, it shall have a free course, and that which hinders the progress of it shall be taken out of the way.

II.He will manifest his favour and grace towards those whose spirits he had stirred up to follow him, as Ezr 1:5. Those who ask the way to Zion he will show the way, and lead in it, Isa 42:16. Those who by nature were blind, and those who, being under convictions of sin and wrath are quite at a loss and know not what to do with themselves, God will lead by a way that they knew not, will show them the way to life and happiness by Jesus Christ, who is the way, and will conduct and carry them on in that way, which before they were strangers to. Thus, in the conversion of Paul, he was struck blind first, and then God revealed his Son in him, and made the scales to fall from his eyes. They are weak in knowledge, and the truths of God at first seem unintelligible; but God will make darkness light before them, and knowledge shall be easy to them. They are weak in duty, the commands of God seem impracticable, and insuperable difficulties are in the way of their obedience; but God will make crooked things straight; their way shall be plain, and the yoke easy. Those whom God brings into the right way he will guide in it. As a type of this, he will lead the Jews, when they return out of captivity, in a ready road to their own land again, and nothing shall occur to perplex or embarrass them in their journey. These are great things, and kind things, very great and very kind; but lest any should say, "They are too great, too kind, to be expected from God by such an undeserving people as that of the Jews, such an undeserving world as that of the Gentiles," he adds, These things will I do unto them, take my word for it I will, and I will not forsake them; he that begins to show this great mercy will go on to do them good.

III.He will particularly put those to confusion who adhere to idols notwithstanding the attempts made by the preaching of the gospel to turn them from idols (Isa 42:17): They shall be turned back, and greatly ashamed, that trust in graven images. The Babylonians shall when they see how the Jews, who despise their images, are owned and delivered by the God they worship without images, and the Gentiles when they see how idolatry falls before the preaching of the gospel, is scattered like darkness before the light of the sun, and melts like snow before its heat. They shall be ashamed that ever they said to these molten images, You are our gods; for how can those help their worshippers who cannot help themselves, nor save themselves from falling into contempt? In times of reformation, when many turn from iniquity, and sin, being generally deserted, becomes unfashionable, it may be hoped that those who will not otherwise be reclaimed will be wrought upon by that consideration to be ashamed of it.

And I will bring the blind by a way that they knew not,.... The Targum interprets this of the people of Israel, thus,

"I will lead the house of Israel, which are like to the blind, in a way which they knew not.''

But it is better to understand it of the Gentiles, who, before the light of the Gospel came among them, were blind as to the true knowledge of God, and especially as in Christ; and of Christ, and the way of peace, life, and salvation by him; and of themselves, and their miserable estate and condition; and of the Spirit of God, and his operations; and of the Scriptures, the Gospel, and the doctrines of it; and which is the case of all men in a state of nature: but the Lord, by his Spirit, opens the eyes of their understandings, and shows them those things they were blind in, and ignorant of, and brings them by a way they knew not before; which way is Christ, the only way to the Father; the way of peace, righteousness, and life; the way to heaven, and eternal happiness: this they knew not before, but thought they must make their own way to God, and their peace with him; must be justified by their own works, and work out their own salvation; but, in conversion, this way to Christ is made known and plain unto them; and in this way the Lord brings all his people to eternal glory:

I will lead them in paths that they have not known; in the paths of duty and truth; in the paths of faith, righteousness, and holiness, and in the ordinances of the Gospel; which they were aliens and strangers to before:

I will make darkness light before them; by going before them himself, as before the children of Israel in a pillar of fire by night; by giving his word to enlighten them; by granting his good Spirit, as a spirit of illumination to them; and by lifting up the light of his countenance on them:

and crooked things straight; remove all obstructions, bear them up under all discouragements, and carry them through all difficulties:

these things will I do unto them, and not forsake them; which may be depended upon, being promised by him that is able to perform, is true, and faithful, and changes not; and, when done, shall not be the last done for them; he will never leave them, nor forsake them, till he has brought them safe to glory.

blind--God's people, Israel, in captivity, needing a guide. In the ulterior sense the New Testament Church, which was about to be led and enlightened by the Son of God as its leader and shepherd in the wilderness of the Roman empire, until it should reach a city of habitation. "A way . . . they knew not," refers to the various means ployed by Providence for the establishment of the Church in the world, such as would never have occurred to the mind of mere man. "Blind," they are called, as not having heretofore seen God's ways in ordering His Church.

make darkness light, &c.--implies that the glorious issue would only be known by the event itself [VITRINGA]. The same holds good of the individual believer (Isa 30:21; Psa 107:7; compare Hos 2:6, Hos 2:14; Eph 5:8; Heb 13:5).