As I live, says the Lord, to me every knee shall bow and every tongue acknowledge God. Romans 14:11, N.E.B.
For what was the great controversy permitted to continue throughout the ages? Why was it that Satan's existence was not cut short at the outset of his rebellion? It was that the universe might be convinced of God's justice in His dealing with evil; that sin might receive eternal condemnation. In the plan of redemption there are heights and depths that eternity itself can never exhaust, marvels into which the angels desire to look. The redeemed only, of all created beings, have in their own experience known the actual conflict with sin; they have wrought with Christ, and, as even the angels could not do, have entered into the fellowship of His sufferings; will they have no testimony as to the science of redemption—nothing that will be of worth to unfallen beings? ...
“In his temple doth everyone speak of his glory” (Psalm 29:9), and the song which the ransomed ones will sing ... will declare the glory of God: “Great and marvelous are thy works, O Lord God, the Almighty; righteous and true are thy ways, thou King of the ages. Who shall not fear, O Lord, and glorify thy name? for thou only art holy” (Revelation 15:3, 4, R.V.).62Education, 308, 309.
As if entranced, the wicked have looked upon the coronation of the Son of God. They see in His hands the tables of the divine law, the statutes which they have despised and transgressed.... Every question of truth and error in the long-standing controversy has now been made plain. The results of rebellion, the fruits of setting aside the divine statutes, have been laid open to the view of all created intelligences. The working out of Satan's rule in contrast with the government of God has been presented to the whole universe. Satan's own works have condemned him. God's wisdom, His justice, and His goodness stand fully vindicated. It is seen that all His dealings in the great controversy have been conducted with respect to the eternal good of His people and the good of all the worlds that He has created.... With all the facts of the great controversy in view, the whole universe, both loyal and rebellious, with one accord declare: “Just and true are thy ways, thou King of saints” (Revelation 15:3).63The Great Controversy, 668-671.
From God's Amazing Grace - Page 373