Sanctification is the means by which God makes us holy, and holiness is the state of having been perfected, purified, and set apart for the purpose of serving and worshiping God. There are three phases of sanctification; one could say that we are sanctified, we are being sanctified, and we will become entirely sanctified. I believe the Bible makes clear that all three of these happen in the life of a believer.
Initial Sanctification
The first phase of sanctification is our spiritual birth, that moment when we make the decision to commit ourselves to follow Christ. Paul wrote in 1 Corinthians 6:11, “But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ and by the Spirit of our God.” When we begin our Christian journey, we are “baptized into Christ Jesus” (Romans 6:3). As John Wesley puts it, “In baptism we, through faith, are ingrafted into Christ; and we draw new spiritual life from this new root, through his Spirit, who fashions us like unto him, and particularly with regard to his death and resurrection” (John Wesley’s Notes on the Bible – Romans 6:3).
To be sanctified is to be set apart from sin and for citizenship in heaven (Philippians 3:20). Our old sinful selves are crucified with Christ (Romans 6:6), and our new sanctified selves are reborn as children of God (John 1:12-13). We are marked by the indwelling of the Spirit as belonging to Christ (Ephesians 1:13).
Gradual Sanctification
The second phase of sanctification is the gradual process of transformation over a lifetime. Sanctification is described in 2 Corinthians 3:18 in the following way: “And we all, with unveiled faces reflecting the glory of the Lord, are being transformed into the same image from one degree of glory to another, which is from the Lord, who is the Spirit.” This is progressive sanctification. The Apostle John also spoke of this when he wrote, “And as we live in God, our love grows more perfect so we will not be afraid on the day of judgment, but we can face him with confidence because we live like Jesus here in this world” (1 John 4:17). Did you catch that? According to this verse, Christ-likeness is not just something we look forward to in the afterlife, but something we can experience and express here and now.
Entire Sanctification
This brings us to the third phase of sanctification that Scripture calls complete holiness, or entire sanctification. It is an apex moment in the sanctifying process both preceded by and followed by gradual sanctification. The gradual work that precedes this instant is our transformation from being sinful in nature, to becoming holy in nature (Hebrews 10:14; Colossians 3:10), while the gradual work after, is God expanding our hearts, so that we may express more and more of His perfect love (1 Thessalonians 3:12-13).
The Sanctified Life
The ultimate state of entire sanctification is complete holiness, and the ultimate expression of entire sanctification is perfect love. Yet, even in complete holiness, we continue to grow more perfect. Consider a student learning to play the piano; they will start with simple exercises and songs, practicing them until they are mastered. The student can then go on to learn more challenging songs until those also are mastered. And this process continues on and on throughout the life of the musician so long as they are pursuing their musicianship. In a similar way, as our faith increases, our capacity to be perfected in Christ-like holiness also increases—as does our expression of God’s perfect love.