"Thus saith God the LORD, he that created the heavens, and stretched them out; he that spread forth the earth, and that which cometh out of it; he that giveth breath unto the people upon it, and spirit to them that walk therein: I the LORD have called thee in righteousness, and will hold thine hand, and will keep thee, and give thee for a covenant of the people, for a light of the Gentiles; To open the blind eyes, to bring out the prisoners from the prison, and them that sit in darkness out of the prison house." (Isaiah 42:5-7)
The Almighty first declares Himself to be the Creator of all, then, under the structure of this authority, He presents the Messiah. The Lord Jesus came in the righteousness of God, because He is God. He had no need for the Pharisaism of His day; and the self-righteousness of the modern-day man is equally distasteful to Him. His own arm brought salvation (Isaiah 63:5). The Father protected every aspect of the Son's ministry. Through every last detail of the Lord's work, God exercised supreme authority and "held" the Son's hand (John 10:18).
The New Covenant sealed by the blood of Christ is that mentioned in the text. The Old Covenant with Israel pointed the way to the Lamb of the New. This is the same covenant mentioned by Jeremiah and the other prophets (Jeremiah 31:31-34). The complete work of this covenant upon the nation of Israel will be realized at the Lord's return. Through the blood of Christ's salvation covenant all peoples of the world have access to redemption. Obviously, the world-wide worship of Jesus Christ in the millennium is the ultimate focus of this light which comes from God and peels away the spiritual blindness of man's heart.
"I am the LORD: that is my name: and my glory will I not give to another, neither my praise to graven images. Behold, the former things are come to pass, and new things do I declare: before they spring forth I tell you of them. Sing unto the LORD a new song, and his praise from the end of the earth, ye that go down to the sea, and all that is therein; the isles, and the inhabitants thereof. Let the wilderness and the cities thereof lift up their voice, the villages that Kedar doth inhabit: let the inhabitants of the rock sing, let them shout from the top of the mountains. Let them give glory unto the LORD, and declare his praise in the islands." (Isaiah 42:8-12)
As the text focuses on Messiah as the supreme and unfailing Servant Whose work brings salvation to mankind, God reminds His audience that He alone is JEHOVAH. No other is like Him (Deuteronomy 6:4). In the Person of the Lord Jesus is found the deity of JEHOVAH God and such glory cannot be shared with any other. Israel's idolatry is denounced along with that of the world; however, the deeper principle is that of God receiving all glory. In the end, He alone will be justified and not mankind. Whether physical idols or spiritual, all that detracts from the glory of God will not stand because His glory cannot be shared or stolen. The life of the redeemed must be centered in giving glory to God and not man.
The Lord reminds Israel of His omniscience. Before Jesus Christ was born, God told Israel and the world of His coming. Before Calvary ever came about, the Lord had predicted such things, and the text is clearly teaching of Israel's redemption even though this event has not been fulfilled. The ability to tell beforehand what will come stands as a witness to God's supremacy.
With an eye toward the world-wide worship of Jesus Christ, the earth's nations are invited to sing praise to the Lord. This language is similar to that found in the millennial song of chapter twelve. Kedar refers to Arabia, and the inhabitants of the rock is possibly a reference to Edom. People who were once bitter enemies of Israel and of the true God will join the worship and praise of the Messiah. "...Many shall come from the east and west, and shall sit down with Abraham, and Isaac, and Jacob, in the kingdom of heaven (Matthew 8:11)."