Glorification is the last link in what the Reformed tradition calls the golden chain of redemption: election, calling, justification, sanctification, and finally glorification, God’s guarantee that everyone He has predestined will be brought all the way home. Paul calls this “God’s wisdom in a mystery,” hidden before the ages for our glory.
The glory of fallen humanity is fading, like the glory that faded from Moses’ face, but the believer’s hope of glory rests on Christ, not on human achievement. Already we are children of God; when He appears, we will be like Him, for we shall see Him as He is. And when Christ returns, He will transform our lowly bodies to be like His own glorious body, by the very power that subjects all things to Himself.