Sanctification is not a passive process. It is a war—a battle against sin, the flesh, and the world. In an era where compromise is celebrated, the believer’s call to holiness is more urgent than ever. While justification is God’s sovereign act of declaring a sinner righteous, sanctification is the lifelong process of becoming conformed to Christ’s image. It is both a divine work and a personal pursuit, a reality accomplished by the Spirit, but requires diligent effort from the believer.
In his book titled, The Mortification of Sin, John Owen famously warned, “Be killing sin, or it will be killing you.”. This is the heart of sanctification: an active fight against sin and a relentless pursuit of godliness.
The doctrine of sanctification is not an academic exercise, but a reality with eternal significance. It is the will of God for every believer (1 Thessalonians 4:3), the means by which we demonstrate our faith (James 2:17), and the evidence that we truly belong to Christ (1 John 2:3-6). Richard Baxter emphasized this necessity, stating, “Holiness is the only way to happiness. The saints must have heaven in them before they are in heaven.” Furthermore, sanctification is not merely an individual pursuit, but one that occurs within the faith community. The local church provides instruction, accountability, and encouragement in the believer’s fight for holiness. As Thomas Watson wrote, “Association begets assimilation. The more we associate with the people of God, the more we shall be like God.”
This article explores the doctrine of sanctification, its eschatological purpose, the dangers of false sanctification, the lifelong battle against sin, and the believer’s ultimate goal of conformity to Christ.
The Eschatological Purpose of Sanctification
Sanctification is not only a present reality but also an eternal one. The term eschatological refers to the study of the last things, particularly God’s redemptive plan, culminating in the believer’s glorification. In other words, sanctification is not simply about daily Christian growth, but about preparing us for the final transformation that occurs when we stand before Christ in glory.
Scripture teaches that the believer’s journey toward holiness will reach its completion in glorification:
- Romans 8:30—”And those whom he predestined he also called, and those whom he called he also justified, and those whom he justified he also glorified.”
- Ephesians 5:25-27—Christ is sanctifying His church so that she will be presented to Him as holy and blameless.
Puritans frequently emphasized this connection between sanctification and glorification. In his book, Heaven on Earth, Thomas Brooks wrote, “Holiness is the bud, and glory is the fruit; holiness is the seed, and glory is the harvest.” In his work, The Grace and Duty of Being Spiritually Minded, John Owen similarly encouraged believers: “Let us labor to grow in grace, for our eternal happiness depends upon it. Grace is but glory begun, and glory is but grace perfected.”
Every trial, discipline, and spiritual battle serves to refine us, preparing us for our eternal inheritance in Christ. The struggles of sanctification are not meaningless; they are forging us into the image of Christ, making us fit for heaven.
The Dangers of False Sanctification
There are two major theological errors that distort the doctrine of sanctification: legalism and antinomianism. These errors represent opposite extremes, yet both are dangerous distortions of biblical holiness.
1. Legalism: The Burden of Self-Righteousness
Legalism teaches that sanctification is achieved through external rules and moral effort, rather than the Spirit’s transforming work. Legalists attempt to earn God’s favor by rigid adherence to laws, creating a spirit of self-righteousness and pride.
- Galatians 3:3 – “Are you so foolish? Having begun by the Spirit, are you now being perfected by the flesh?”
- Colossians 2:23 – “These have indeed an appearance of wisdom in promoting self-made religion and asceticism… but they are of no value in stopping the indulgence of the flesh.”
John Bunyan warned, “A man may wear out his life in a legal spirit and never see heaven. True sanctification flows from the Spirit, not the letter of the law.”
2. Antinomianism: Perverting Grace
On the opposite end, antinomianism (anti = against, nomos = law) rejects the necessity of obedience, claiming that grace eliminates the need for holiness. This error promotes spiritual complacency and licentiousness.
- Jude 4 – “Certain people have crept in unnoticed who long ago were designated for this condemnation, ungodly people, who pervert the grace of our God into sensuality and deny our only Master and Lord, Jesus Christ.”
The true gospel calls believers to walk in obedience, not as a means of salvation, but as its necessary fruit (James 2:17).
The Battle Against Sin: A Lifelong War
Sanctification is a war. The believer is engaged in an ongoing struggle against the flesh, the world, and the devil.
- Romans 7:18-25—Even the Apostle Paul described the ongoing battle with sin.
- Galatians 5:16-17— “Walk by the Spirit, and you will not gratify the desires of the flesh.”
- Ephesians 6:11-13—The armor of God is essential for spiritual warfare.
Thomas Watson wrote, “The first step in mortification is to know that we have sin; the second step is to fight against it daily.”. Victory over sin does not come through passivity, but through daily, Spirit-empowered battle.
The Goal of Sanctification: Conformity to Christ
The ultimate purpose of sanctification is to be conformed to the image of Christ:
- Romans 8:29 – “For those whom he foreknew he also predestined to be conformed to the image of his Son.”
- 2 Corinthians 3:18 – “Beholding the glory of the Lord, we are being transformed into the same image from one degree of glory to another.”
Jonathan Edwards captured this vision: “The more holiness we have, the more we shall see of God.” Sanctification is not about self-improvement, but about growing in Christlikeness.
Final Exhortation: The Call to Holiness
Sanctification is not optional for the believer. It is God’s will:
- Hebrews 12:14 – “Strive for… the holiness without which no one will see the Lord.”
- Philippians 1:6 – “He who began a good work in you will bring it to completion.”
John Owen urged, “There is no safety against sin but in a constant warfare.” The believer must fight, knowing that God is faithful to complete the work He has begun. Let us press on, pursuing holiness with zeal and endurance.
