The Christian path is entered by the gateway of justification; its course is sanctification; its destination is glorification. While these are inseparable, they are also distinct.
Justification is a gift, a once-for-all act of God done for us by which the sinner’s life in the old path is brought to an end, and his feet set in the new one. It delivers from the guilt of sin and declares the believer to be righteous.
Sanctification is a process by which God works in the believer by His Spirit from his entering the Christian path until its end. This work is done to us, setting apart unto holiness, delivering more and more from the power of sin.
Glorification is a heavenly experience, that act of God by which the justified man completes his journey and enters into full possession of eternal glory, delivered from the presence of sin. —George E. Harpur (adapted)