The short answer is that “glorification” is God’s final removal of sin from the life of the saints (i.e., everyone who is saved) in the eternal state (Romans 8:18; 2 Corinthians 4:17). At Christ’s coming, the glory of God (Romans 5:2)—His honor, praise, majesty, and holiness—will be realized in us; instead of being mortals burdened with sin nature, we will be changed into holy immortals with direct and unhindered access to God’s presence, and we will enjoy holy communion with Him throughout eternity. In considering glorification, we should focus on Christ, for He is every Christian’s “blessed hope”; also, we may consider final glorification as the culmination of sanctification.
Final glorification must await the manifestation of the glory of our great God and Savior Jesus Christ (Titus 2:13; 1 Timothy 6:14). Until He returns, we are burdened with sin, and our spiritual vision is distorted because of the curse. “For now we see in a mirror dimly, but then face to face. Now I know in part; then I shall know fully, even as I have been fully known” (1 Corinthians 13:12). Every day, we should be diligent by the Spirit to put to death what is “fleshly” (sinful) in us (Romans 8:13).
How and when will we be finally glorified? At the last trumpet, when Jesus comes, the saints will undergo a fundamental, instant transformation (“we shall all be changed, in a moment, in the twinkling of an eye” – 1 Corinthians 15:51); then the “perishable” will put on the “imperishable” (1 Corinthians 15:53). Yet 2 Corinthians 3:18 clearly indicates that, in a mysterious sense, “we all,” in the present, “with unveiled face” are “beholding the glory of the Lord” and are being transformed into His image “from one degree of glory to another” (2 Corinthians 3:18). Lest anyone imagine that this beholding and transformation (as part of sanctification) is the work of especially saintly people, the Scripture adds the following bit of information: “For this comes from the Lord who is the Spirit.” In other words, it is a blessing bestowed on every believer. This does not refer to our final glorification but to an aspect of sanctification by which the Spirit is transfiguring us right now. To Him be the praise for His work in sanctifying us in the Spirit and in truth (Jude 24-25; John 17:17; 4:23).
We should understand what Scripture teaches about the nature of glory—both God’s unsurpassed glory and our share in it at His coming. God’s glory refers not merely to the unapproachable light that the Lord inhabits (1 Timothy 6:15-16), but also to His honor (Luke 2:13) and holiness. The “You” referred to in Psalm 104:2 is the same God referenced in 1 Timothy 6:15-16; He is “clothed with splendor and majesty,” covering Himself “with light as with a garment” (Psalm 104:2; cf. 93:1; Job 37:22; 40:10). When the Lord Jesus returns in His great glory to execute judgment (Matthew 24:29-31; 25:31-35), He will do so as the only Sovereign, who alone has eternal dominion (1 Timothy 6:14-16).
Created beings dare not gaze upon God’s awesome glory; like Ezekiel (Ezekiel 1:4-29) and Simon Peter (Luke 5:8), Isaiah was devastated by self-loathing in the presence of the all-holy God. After the seraphim proclaimed, “Holy, holy, holy is the Lord of hosts; the whole earth is full of his glory!” Isaiah said, “Woe is me! For I am lost; for I am a man of unclean lips, and I dwell in the midst of a people of unclean lips; for my eyes have seen the King, the Lord of hosts!” (Isaiah 6:4). Even the seraphim showed that they were unworthy to gaze upon the divine glory, covering their faces with their wings.
God’s glory may be said to be “heavy” or “weighty”; the Hebrew word kabod literally means “heavy or burdensome”; Most often, the Scriptural usage of kabod is figurative (e.g., “heavy with sin”), from which we get the idea of the “weightiness” of a person who is honorable, impressive, or worthy of respect.
When the Lord Jesus became incarnate, He revealed both the “weighty” holiness of God and the fullness of His grace and truth (“and the Word became flesh and dwelt among us, and we have seen his glory, glory as of the only Son from the Father, full of grace and truth” [John 1:14; cf. 17:1–5]). The glory revealed by the incarnate Christ accompanies the ministry of the Spirit (2 Corinthians 3:7); it is unchanging and permanent (Isaiah 4:6-7; cf. Job 14:2; Psalm 102:11; 103:15; James 1:10). The previous manifestations of God’s glory were temporary, like the fading effluence of God’s glory from Moses’ face. Moses veiled his face so that the hard-hearted Israelites might not see that the glory was fading (1 Corinthians 3:12), but in our case the veil has been removed through Christ, and we reflect the glory of the Lord and seek by the Spirit to be like Him.
In His high priestly prayer, the Lord Jesus requested that God would sanctify us by His truth (i.e., make us holy; John 17:17); sanctification is necessary if we are to see Jesus’ glory and be with Him in eternal fellowship (John 17:21-24). “Father, I desire that they also, whom you have given me, may be with me where I am, to see my glory that you have given me because you loved me before the foundation of the world” (John 17:24). If the glorification of the saints follows the pattern revealed in Scripture, it must entail our sharing in the glory (i.e., the holiness) of God.
According to Philippians 3:20–21, our citizenship is in heaven, and when our Savior returns He will transform our lowly bodies “to be like His glorious body.” Although it has not yet been revealed what we shall be, we know that, when He returns in great glory, we shall be like Him, for we shall see Him as He is (1 John 3:2). We will be perfectly conformed to the image of our Lord Jesus and be like Him in that our humanity will be free from sin and its consequences. Our blessed hope should spur us on to holiness, the Spirit enabling us. “Everyone who thus hopes in Him purifies himself as He is pure” (1 John 3:3).