Mortify
What Does It Mean to Mortify?
The English word "mortify" appears in older Bible translations like the King James Version (Romans 8:13; Colossians 3:5) but is largely obsolete in modern usage. Contemporary translations, such as the ESV and NASB, render the underlying Greek verbs (thanatoō and nekroō) as "put to death" or "make dead." This is not about physical death but a spiritual, decisive action against sin. To mortify is to actively and intentionally starve, weaken, and ultimately kill the sinful habits, desires, and patterns that remain in a believer's life after conversion. It is the believer's responsibility, empowered by God's Spirit, to attack sin at its root.
The Biblical Foundation for Mortification
The call to mortify sin flows directly from the gospel. The Apostle Paul grounds this command in the believer's new identity. In Romans 8:12-13, he argues that because we are no longer debtors to the flesh but have received the Spirit of adoption, we are obligated to put to death the misdeeds of the body. Similarly, in Colossians 3:1-10, the command to "put to death" earthly practices (Colossians 3:5) follows the declaration that the believer has died with Christ and been raised to new life with Him (Colossians 3:1-4). Mortification is not how one earns salvation; it is the necessary response of someone who has already been transferred from the kingdom of darkness into the kingdom of God's beloved Son (Colossians 1:13). It is the practical working out of a death that has already occurred positionally in Christ.
The Process and Means of Mortification
Mortification is not a one-time event but a lifelong, daily discipline. It involves both a decisive rejection and an ongoing battle. The New Testament provides a clear framework for this process. First, it requires honest recognition and conviction of specific sins, as Paul lists examples like sexual immorality, impurity, passion, evil desire, and covetousness (Colossians 3:5). Second, it is a Spirit-empowered endeavor. Paul explicitly states in Romans 8:13 that it is "by the Spirit" that we put to death the deeds of the body. Human willpower alone is insufficient. Third, mortification is paired with vivification—the putting on of Christ-like virtues. Colossians 3 instructs believers to "put off" the old self and its practices and to "put on" the new self, characterized by compassion, kindness, humility, and love (Colossians 3:9-14). The negative action of killing sin is incomplete without the positive action of cultivating godliness.
Historical and Theological Development
The concept of mortification has been a central theme in Christian spirituality throughout history. The early church fathers, like Augustine, wrote extensively on the battle against concupiscence (sinful desire). During the Reformation, theologians such as John Calvin emphasized mortification as a key component of repentance and sanctification. The Puritan writers of the 16th and 17th centuries produced profound and practical works on the subject, with John Owen's treatise "The Mortification of Sin" being a classic example. Owen famously wrote, "Be killing sin or it will be killing you." This historical focus underscores that mortification was never seen as a marginal or optional spiritual practice but as essential to genuine Christian living. It countered both moral laxity and any notion of passive perfectionism, affirming the reality of both grace and the ongoing struggle with indwelling sin.
Significance for Modern Believers
In a modern context that often minimizes personal responsibility for sin or reduces holiness to psychological self-improvement, the biblical call to mortify remains vital and counter-cultural. It guards against a cheap grace that ignores the call to obedience (Romans 6:1-2). It provides a robust, realistic framework for dealing with persistent sin, offering hope through the Spirit's power rather than leaving believers in guilt or despair. Furthermore, it directs spiritual growth away from vague religiosity toward concrete, specific action against identifiable sins. Ultimately, mortification is an act of worship and love—putting to death what dishonors God and harms ourselves and others, thereby making more room for the life and character of Christ to be manifested. It is the practical proof of a living faith, demonstrating that our union with Christ in His death and resurrection has real, transformative power in our daily conduct.
Biblical Context
The concept of mortification appears primarily in the Pauline epistles of the New Testament. The two key passages are Romans 8:13 and Colossians 3:5. In Romans, the command is set within Paul's larger argument about life in the Spirit versus life in the flesh, following his explanation of the believer's freedom from the law of sin and death. In Colossians, it is part of the ethical exhortation (parenesis) that flows from the profound Christological teaching of the letter's first two chapters. The language of "putting off" the old self and "putting on" the new, found in Ephesians 4:22-24 and Colossians 3, is conceptually linked to mortification. The role it plays is to define the believer's active participation in the process of sanctification following justification.
Theological Significance
Mortification is theologically significant because it clarifies the relationship between divine grace and human responsibility in sanctification. It teaches that salvation, while entirely of grace, produces an active, obedient response. It underscores the realistic New Testament view of the Christian life as a war against remaining sin, even in the redeemed. Theologically, it highlights the believer's union with Christ: we are called to put sin to death because we have already died with Christ (Romans 6:1-11; Colossians 3:3). It reveals God's purpose not only to forgive sin but to destroy its power in the lives of His people, making them progressively more like Jesus. It is a doctrine that balances the indicative (what God has done) with the imperative (what we must do in response).
Historical Background
The Greek verbs used (thanatoō and nekroō) were strong, physical terms in the first-century world. Thanatoō means to put to death, execute, or condemn to death. Nekroō means to make dead, deprive of life, or destroy strength. Paul's use of this stark language would have been striking to his original audience. Culturally, his lists of vices to "put to death" (e.g., in Colossians 3:5, 8) directly confronted common practices in the Greco-Roman world, such as sexual license, greed, and malicious speech. His teaching provided a radical new ethical framework for converts coming from pagan backgrounds. Extra-biblical sources, like the Dead Sea Scrolls, show that the Qumran community also used militant language for spiritual warfare, but Paul's teaching is distinct in its grounding in the finished work of Christ and the indwelling power of the Holy Spirit.