Mortification of Sin
As taught in the Reformed / Presbyterian tradition
The daily struggle to put to death the deeds of the flesh by the power of the Spirit.
The doctrine of the mortification of sin stands as one of the most distinctive and rigorous pillars of the Reformed tradition’s understanding of Christian ethics and the life of the believer. At its core, this subtopic answers a fundamental question: How does a person who has been declared righteous by God (justified) live in a world where the remains of indwelling sin continue to wage war against the soul? In the Reformed view, the Christian life is not a static state of arrival but a dynamic, often violent, spiritual conflict. Mortification is the "negative" aspect of sanctification—the process by which the believer, empowered by the Holy Spirit, seeks to weaken, subdue, and eventually destroy the power of remaining sin in their life. It is the "killing" of sin so that the new life in Christ might flourish.
By the end of this lesson
- **Identify** the biblical and theological definitions of "mortification" and "vivification" within the Reformed system of sanctification.
- **Distinguish** between evangelical mortification (driven by the Spirit and the Gospel) and legalistic mortification (driven by fear and human effort).
- **Explain** the role of the Holy Spirit as the primary agent of mortification and the believer’s responsibility as a secondary, dependent agent.
- **Articulate** the relationship between union with Christ and the power to overcome indwelling sin.
- **Trace** the historical development of the doctrine from the Westminster Standards through the writings of John Owen and modern Reformed teachers.
- **Defend** the necessity of mortification for the maintenance of spiritual assurance and the "quietness" of the conscience.
- **Apply** the "means of grace" (Word, Prayer, Sacraments) to the practical task of identifying and weakening specific "besetting sins."
- **Compare** the Reformed view of the "struggle" with sin against perfectionist traditions that claim a higher state of sinlessness is possible in this life.
Scripture
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