What is sanctification, and how is it related to our union with Christ?

Sanctification is not a project of self-improvement, nor is it a matter of accumulating moral achievements to present before God. The prevailing definition—“being set apart for God’s purposes and made holy”—is only true if we understand that holiness is not the result of our striving, but of Christ’s presence. The entire work of sanctification is God filling the believer with Christ Himself. Holiness is not a standard you reach by law-keeping; it is the outcome of being filled with the One who is holy.

Holiness: Not Performance, But Presence

We default to thinking that “holy” means “sinless,” and that God’s purpose is simply to eradicate our sin. But Scripture is clear: the destruction of sin is a byproduct of Christ being manifested in us (1 John 3:5). The more you attempt to achieve holiness through your own effort—by gathering up your sins and trying to “clean up” your life—the more you will find yourself overwhelmed by sin’s presence (Romans 7:18-19). Law-keeping and moral performance do not sanctify; they only increase your awareness of failure and futility.

Holiness and sanctification are not possible apart from Christ Himself (John 15:5). God’s intention is not merely to “clean you up,” but to fill you with Christ. This is not a secondary matter; to substitute self-effort for Christ’s presence is to undermine the very foundation of justification and sonship. If sanctification is reduced to your performance, you have abandoned the inheritance of the New Covenant and returned to the futility of the flesh.

The Burnt Offering: The True Basis of Sanctification

Consider the burnt offering: it was not the quality of the animal that made the altar holy, but the blood that sanctified the altar. Whatever touched that altar—regardless of its intrinsic worth—became “most holy” (Leviticus 6:18). This is a picture of our union with Christ. The altar, sanctified by the blood, represents Christ’s absolute devotion and obedience, His sacrifice of love, and His dedication to the Father’s will. The fragrance that rose from the altar was pleasing to God—not because of the offerer, but because of the offering.

If you try to “gather up” your sins and burn them yourself, you will find you cannot start the fire. God alone provided the fire at the cross, where Christ condemned sin in His flesh (Romans 8:3). He became sin, became the curse, and died to sin once for all (Galatians 3:13; Romans 6:10). Now, Christ is supplied to us as the life-giving Spirit. The cleansing is accomplished not by your effort, but by the manifestation of Christ in you.

The Spirit: Living Water, Not Dead Works

When you believed the gospel, you received Christ’s Spirit as a fountain of living water (John 4:14; 7:38-39). This Spirit does not merely “wash” you in a legal sense; He fills you, satisfies your thirst, and continually renews you. The ashes and water from the burnt offering (Numbers 19:1-10) point to this dual reality: the finished work of Christ removes what is dead, and the living water of the Spirit brings ongoing cleansing and satisfaction.

Sanctification is not a process of incremental self-improvement. It is the result of God’s action—filling you with Christ, making you a vessel for His life and fragrance (2 Corinthians 4:7; Ephesians 5:26-27). The Spirit’s presence in you is the guarantee of your inheritance (Galatians 3:14), the source of continual cleansing, and the means by which you are transformed into Christ’s image (2 Corinthians 3:18).

What Is Lost If We Accept the Error?

If you accept the lie that sanctification is achieved by your own effort—by law-keeping, moral resolve, or religious performance—you lose everything that Christ accomplished. You forfeit the rest and assurance of sonship, and you place yourself under the curse of the law. The inheritance is not for those who labor in the flesh, but for those who receive the Spirit by faith (Galatians 3:2-5). To make sanctification about your performance is to reject the very purpose of God: the manifestation of Christ in you as His holy vessel. You cannot have justification by faith and sanctification by works; to attempt it is to collapse the gospel itself.

The True Goal: Manifesting Christ

God’s purpose is not simply to have a people who are “cleaned up,” but a people who are filled with Christ and manifest Him. Holiness is not the means to this end—it is the result. As Christ is manifested in you, you are transformed, your heart is renewed, and your life emits a fragrance pleasing to God (Ephesians 5:2; 2 Corinthians 2:15). This is not your doing; it is the outworking of the Spirit of Sonship, bringing you into the atmosphere of love and fellowship with God (1 John 1:7).

God’s intention is not just to “clean us up,” but to fill us with Christ, and this is how He “cleans us up!” (Ephesians 3:19; Colossians 3:10)

No Sanctification Without Christ

It is impossible to be sanctified and miserable, weighed down by unbelief and the burden of self-effort. Sanctification is Christ Himself. To be sanctified is to be filled with the joy, rest, and assurance that comes from His indwelling life. The only way to holiness is through union with Christ, not through the patchwork of your own works.

Reject the counterfeit. Sanctification is not a ladder you climb; it is the inheritance you receive. It is not your striving, but your union with Christ, that makes you holy and fulfills God’s purpose for you. Anything less is not sanctification at all.

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