Sanctification in the Westminster Confession: Chapter XIII and Growth in Grace

The Westminster Confession of Faith devotes its thirteenth chapter to sanctification — the ongoing work of God's grace in the lives of those who have been justified. Coming after the foundational chapters on effectual calling and justification, chapter XIII makes clear that salvation is not merely a legal declaration but a transformative reality. Those whom God justifies, he also progressively transforms.

The Confession opens with a precise statement of what sanctification is and who accomplishes it: 'They who are effectually called and regenerated, having a new heart and a new spirit created in them, are further sanctified, really and personally, through the virtue of Christ's death and resurrection, by his Word and Spirit dwelling in them.' Sanctification is 'real and personal' — it involves actual change in character, not merely a changed legal status. It comes through 'the virtue of Christ's death and resurrection,' meaning the same events that justify also sanctify. And it comes through 'the Word and Spirit' — the ordinary means of grace are the instruments of transformation.

The Confession is equally realistic about the nature of sanctification in this life. It acknowledges that 'the dominion of the whole body of sin is destroyed, and the several lusts thereof are more and more weakened and mortified' — but also that 'a remnant of corruption' remains in every part of the believer, giving rise to 'a continual and irreconcilable war.' The Christian life is not one of achieved perfection but of ongoing struggle and growth. The Confession explicitly rejects any perfectionism that claims believers can attain a state of sinlessness in this life.

This realistic account has important pastoral implications. The ongoing presence of sin in a believer's life is not evidence that they were never saved; it is evidence that they are in the battle every regenerate person fights. The Confession's language of 'continual and irreconcilable war' is not pessimistic but honest — and ultimately hopeful, because it is a war in which the believer, empowered by the Spirit, will ultimately prevail.

The means by which sanctification progresses are those the Westminster Standards consistently emphasize: the Word, prayer, the sacraments, the fellowship of the church, and the practice of Christian discipline. Chapter XIII does not describe sanctification as a passive experience that happens apart from human effort. The believer is called to 'cleanse himself from all filthiness of the flesh and spirit, perfecting holiness in the fear of God' (2 Corinthians 7:1) — while recognizing that even that effort is sustained and enabled by the Spirit of God.

Chapter XIII closes by acknowledging that sanctification in this life is always incomplete. The imperfection of our sanctification is why we continue to need justification — to stand before God in the perfect righteousness of Christ rather than our own. But incomplete does not mean absent. The Confession envisions genuine and progressive growth in grace — a movement toward conformity to Christ that will reach its completion only in glorification, when we shall see him as he is and be made fully like him.