Sanctification, the process of becoming more like Christ, is at the heart of Paul David Tripp and Timothy S. Lane’s book How People Change. This process is often misunderstood as mere behavior modification—trying harder, following rules, or doing more. But Tripp and Lane offer a refreshing perspective: sanctification is not about what we do to change ourselves but about what God is doing in us through the gospel.
At its core, sanctification is about heart transformation. The authors explain that lasting change doesn’t come from addressing surface-level behaviors; it comes from addressing the deeper issues of the heart. Our actions, attitudes, and struggles are always rooted in what we believe, desire, and value most. Sanctification happens when the gospel reshapes those core beliefs and desires, enabling us to live out the truth of who we are in Christ.
One of the key insights in How People Change is the recognition that life’s challenges—what Tripp calls the “heat” of life—are not obstacles to sanctification but tools God uses to shape us. Difficult circumstances, conflicts, and trials reveal what’s really going on in our hearts. Do we respond to “heat” with sinful “thorns” like anger, fear, or despair? Or do we bear the “fruit” of the Spirit, trusting God and reflecting Christ’s character?
The authors emphasize that sanctification is not about trying harder to bear fruit but about abiding in Christ. The gospel reminds us that our identity is secure: we are loved, forgiven, and empowered by God’s Spirit. This assurance frees us to confront our sin honestly, without fear of condemnation, and to rely on God’s grace for change. Tripp and Lane call this process “gospel transformation”—change that begins with the heart and flows outward into every area of life.
Sanctification also requires a shift in how we see ourselves. Many Christians approach sanctification as a self-improvement project, believing that their worth is tied to their performance. But Tripp and Lane challenge this mindset, showing that sanctification is not about proving ourselves to God. Instead, it’s about surrendering to His work in us. The gospel frees us from striving and invites us to rest in the reality that Christ’s work is enough.
Another essential element of sanctification highlighted in How People Change is community. Tripp and Lane argue that God never intended for sanctification to be a solo endeavor. The church is a vital context for growth, where believers speak truth into one another’s lives, offer encouragement, and confront sin with grace. Honest, gospel-centered relationships are crucial for helping us see blind spots, apply Scripture, and stay accountable in the pursuit of Christlikeness.
Finally, Tripp reminds us that sanctification is a process. It’s not instantaneous or linear but a lifelong journey of becoming who God created us to be. The good news is that God is committed to this work. Philippians 1:6 assures us that “He who began a good work in you will bring it to completion at the day of Jesus Christ.”
In How People Change, Tripp and Lane offer a rich, gospel-centered vision of sanctification: a heart-level transformation fueled by grace, shaped by God’s Word, and sustained in community. Sanctification isn’t about what we do—it’s about what God is doing in us through His Spirit, for His glory.
If you would like to explore this new study, it is available on Amazon, as well as part of Good Questions Have Groups Talking,
