Sanctification

“And we all, with unveiled face, beholding the glory of the Lord, are being transformed into the same image from one degree of glory to another. For this comes from the Lord who is the Spirit.” — 2 Corinthians 3:18

Hagiasmos (ἁγιασμός) means “sanctification” or “holiness” — the process and state of being made holy, set apart for God. The related verb hagiazo (ἁγιάζω) means “to make holy” or “to consecrate.” Both are rooted in the Hebrew qadash (קָדַשׁ), “to set apart, consecrate,” whose adjective form qadosh (קָדוֹשׁ) describes God’s own separateness and moral purity. To be sanctified is to be drawn into the holiness of God Himself.

Positional Sanctification

At the moment of faith and union with Christ, the believer is declared holy — set apart as belonging to God. Paul addresses the Corinthian church, with all its struggles, as “those sanctified in Christ Jesus, called to be saints” (1 Corinthians 1:2). The word “saints” is hagioi (ἅγιοι) — literally “holy ones” — a term of identity, not achievement. The author of Hebrews writes that “we have been sanctified through the offering of the body of Jesus Christ once for all” (Hebrews 10:10).

This positional reality is foundational. The believer’s identity is no longer defined by sin but by Christ. It is a finished work, grounded in the cross, not in human achievement. Positional sanctification is inseparable from justification — the declared righteous standing and the declared holy identity are two facets of the one act by which God claims sinners as His own (1 Corinthians 6:11).

Progressive Sanctification

While believers are already holy in their standing before God, they are also being made holy in their daily lives. This is the ongoing, lifelong process of growth in godliness. Paul prays that God would “sanctify you entirely” (1 Thessalonians 5:23) and urges believers to apotithemi (ἀποτίθημι), “to put off, lay aside,” the old self and endyo (ἐνδύω), “to clothe oneself in, put on,” the new self, created after the likeness of God in true righteousness and holiness (Ephesians 4:22–24).

Progressive sanctification involves:

• Renewal of the mind — Transformation through the anakainosis (ἀνακαίνωσις) — “renewal, renovation” — of the nous (νοῦς), the mind’s capacity for understanding, judgment, and moral perception (Romans 12:2)
• Mortification of sin — Thanatoo (θανατόω), “to put to death,” describes the believer’s active, Spirit-empowered killing of sinful patterns and desires (Romans 8:13; Colossians 3:5)
• Cultivation of virtue — Growing in the fruit of the Spirit: love, joy, peace, patience, kindness, goodness, faithfulness, gentleness, and self-control (Galatians 5:22–23)
• Deepening communion with God — Increasing knowledge of and fellowship with Christ (Philippians 3:10; cf. union with God)

Final Sanctification (Glorification)

The New Testament looks forward to a day when sanctification is complete. At the return of Christ, believers will be fully conformed to His image — body, soul, and spirit made whole. “When he appears we shall be like him, because we shall see him as he is” (1 John 3:2). Paul calls this the apolytrosis (ἀπολύτρωσις) — “redemption, release through ransom” — of our bodies (Romans 8:23), the culmination of God’s predestining purpose (Romans 8:29–30).

The Role of the Holy Spirit

Sanctification is supremely the work of the Holy Spirit. It is the Spirit who convicts of sin (John 16:8), who produces fruit in the believer’s life (Galatians 5:22–23), and who transforms believers into Christ’s image “from one degree of glory to another” (2 Corinthians 3:18). Paul calls the Spirit “the Spirit of holiness” (Romans 1:4) and identifies sanctification as the Spirit’s specific ministry (2 Thessalonians 2:13; 1 Peter 1:2).

Human Responsibility

Sanctification is God’s work, yet it requires genuine human participation. The classic text is Philippians 2:12–13: “Work out your own salvation with fear and trembling, for it is God who works in you, both to will and to work for his good pleasure.” Believers are called to active obedience — not to earn God’s favor, but because God’s grace empowers and motivates their effort.

Scripture uses vigorous language: dioko (διώκω), “pursue, press hard after,” for holiness (Hebrews 12:14); hypopiazo (ὑποπιάζω), “to strike under the eye, to discipline severely,” the body (1 Corinthians 9:27); agonizomai (ἀγωνίζομαι), “to contend, struggle in competition,” the good fight of the faith (1 Timothy 6:12). Grace does not produce passivity but energized, Spirit-empowered effort.

Theological Perspectives

Christian traditions understand the dynamics of sanctification in different ways:

• Reformed tradition — Emphasizes sanctification as the definite, progressive work of God’s grace in which the believer cooperates but never achieves sinless perfection in this life. The struggle with indwelling sin remains until glorification (Romans 7:14–25). The Westminster Confession (XIII) describes sanctification as “throughout, in the whole man,” yet “imperfect in this life” — there remain “remnants of corruption in every part.”
• Catholic tradition — Teaches that sanctification is a real, interior transformation — not merely a change of status but an infusion of grace that makes the soul genuinely holy. The sacraments, especially the Eucharist and confession (reconciliation), are the ordinary means by which sanctifying grace is received and restored. The Council of Trent (Session VI, 1547) affirmed that justification itself includes sanctification — being “not only reputed but truly called and made just.” Catholic theology also recognizes that some saints attain heroic holiness through extraordinary cooperation with grace.
• Wesleyan tradition — Affirms progressive sanctification but also teaches the possibility of “entire sanctification” or Christian perfection in this life — not absolute sinlessness, but a heart wholly devoted to love of God and neighbor, made possible by a distinct work of grace (cf. Deuteronomy 30:6; Matthew 22:37). Wesley drew on both the Fathers and Scripture to argue that what God commands, He also enables.
• Eastern Orthodox tradition — Speaks of sanctification through the lens of theosis (θέωσις) — deification or participation in the divine nature (2 Peter 1:4). Athanasius’s axiom captures the vision: “God became man that man might become god” (De Incarnatione). Through the sacraments, prayer, and ascetic life, believers are progressively united with God’s uncreated energies, becoming by grace what God is by nature, without confusion of divine and human natures.

Each tradition affirms that holiness is both God’s gift and the believer’s calling, that the Spirit is the primary agent of transformation, and that the goal is ever-deeper union with God through Christ.

“Now may the God of peace himself sanctify you completely, and may your whole spirit and soul and body be kept blameless at the coming of our Lord Jesus Christ. He who calls you is faithful; he will surely do it.” — 1 Thessalonians 5:23–24