Christians still sin because becoming a follower of Jesus does not instantly remove the believer’s fallen human nature. When a person trusts in Christ, they are truly forgiven, justified, and spiritually made new (2 Cor. 5:17), but they are not yet perfected. Until the resurrection, Christians continue to live in mortal bodies affected by the ongoing presence of sin (Rom. 7:14–25).
The New Testament teaches that believers are simultaneously declared righteous in Christ and yet still engaged in a lifelong battle against the flesh. Christians are no longer slaves to sin (Rom. 6:6–14), but sin’s presence remains an active reality in this life. This is why even mature believers continue to struggle, repent, and depend daily on God’s grace.
One of the clearest passages on this issue is Romans 7, where the apostle Paul describes his own struggle with sin:
“For I do not do the good I want, but the evil I do not want is what I keep on doing.” (Rom. 7:19)
Christians throughout history have debated some details of this passage, but the broader point is unmistakable: believers experience an internal conflict between the desires of the Spirit and the desires of the flesh.
The New Testament uses the word “flesh” (Greek: sarx) not merely to describe the physical body but humanity in its fallen, sin-corrupted condition. Even after conversion, believers still contend with lingering sinful desires, habits, fears, pride, selfishness, lust, anger, and weakness. Paul describes this conflict in Galatians:
“For the desires of the flesh are against the Spirit, and the desires of the Spirit are against the flesh.” (Gal. 5:17)
This tension helps explain why Christians can genuinely love Christ and still fail Him at times.
Importantly, Christianity does not teach that believers remain unchanged. The Bible speaks of salvation in three related dimensions:
- Christians have been saved from sin’s penalty (justification).
- Christians are being saved from sin’s power (sanctification).
- Christians will be saved from sin’s presence entirely (glorification).
That middle category—sanctification—is the lifelong process by which the Holy Spirit gradually transforms believers into the likeness of Christ (Rom. 8:29). Growth in holiness is real, but it is usually progressive rather than instantaneous.
This is why the New Testament repeatedly calls Christians to ongoing repentance, confession, spiritual warfare, prayer, and perseverance. Believers are not passive in this struggle. Scripture commands Christians to “put to death” sinful behavior (Col. 3:5), resist temptation (James 4:7), and walk by the Spirit (Gal. 5:16).
At the same time, the Christian’s standing before God does not rest on achieving sinless perfection. Our hope rests entirely on Christ’s righteousness credited to us through faith (Rom. 4:5–8). This is crucial because many Christians become discouraged when they continue struggling with sin after conversion. Ironically, the very grief believers feel over sin is often evidence of spiritual life. Before conversion, people are typically comfortable in their sin. After conversion, the Spirit convicts us and produces a growing desire for holiness.
The apostle John holds both truths together beautifully. On one hand, he says:
“If we say we have no sin, we deceive ourselves.” (1 John 1:8)
But he also says:
“No one born of God makes a practice of sinning.” (1 John 3:9)
John is not contradicting himself. Christians still commit sins, but they no longer live in unbroken, unrepentant rebellion as a settled pattern of life. Genuine believers struggle against sin rather than making peace with it.
Historically, Christians have sometimes fallen into two opposite errors on this issue. One error is perfectionism—the idea that Christians can reach complete sinlessness in this life. The other is antinomianism—the idea that obedience and holiness no longer matter because of grace. The New Testament rejects both extremes. Christians are fully justified by grace alone, yet that grace also produces transformation and obedience over time (Titus 2:11–14).
One final point is worth emphasizing: Christians do not battle sin alone. The Holy Spirit indwells believers, convicts them, strengthens them, and continually points them back to Christ. The Christian life is not about achieving moral perfection through sheer willpower. It is about ongoing dependence upon Jesus.
Key Scriptures to Study #
- Romans 7:14–25 — Paul describes the believer’s struggle with sin.
- Galatians 5:16–25 — The conflict between the flesh and the Spirit.
- 1 John 1:8–9 — Christians still sin and must confess their sins.
- Romans 6:1–14 — Believers are no longer slaves to sin.
- Philippians 1:6 — God continues His sanctifying work in believers.
Objections & Misconceptions #
Common Objection: “If Christians still sin, how are they any different from non-Christians?”
The difference is not sinless perfection but a fundamentally changed relationship to sin. Christians are forgiven, indwelt by the Holy Spirit, reconciled to God, and progressively transformed. They now fight against sin rather than embrace it as their identity and master.
Common Objection: “Does ongoing sin mean someone is not truly saved?”
Persistent, hardened, unrepentant rebellion can indeed call a profession of faith into question (1 John 3:6–10). But genuine believers do still struggle and stumble. The issue is not whether Christians ever sin, but whether they continue repenting and trusting in Christ.
Common Objection: “Why doesn’t God simply remove all sinful desires immediately?”
Scripture does not give a complete answer, but sanctification appears to be part of God’s process of shaping believers into deeper humility, dependence, perseverance, and holiness (Rom. 5:3–5; James 1:2–4).
Why This Matters #
Many Christians become discouraged when they continue battling sin after coming to faith. Some wrongly conclude they are not truly saved because the struggle continues. But the New Testament actually expects this struggle.
Understanding the biblical doctrine of sanctification protects believers from both despair and pride. It reminds us that our salvation rests on Christ’s finished work, not our flawless performance. At the same time, it calls us to take holiness seriously and continue growing in obedience.
Most importantly, this doctrine keeps the Christian’s eyes fixed on Jesus. Our hope is not that we have become perfect, but that Christ is perfectly righteous on our behalf—and that one day He will fully complete the work He began in us (Phil. 1:6).
Recommended Resources #
- Mere Christianity — by C. S. Lewis. Excellent discussion of Christian transformation and moral struggle.
- The Pursuit of Holiness — by Jerry Bridges. Practical and balanced treatment of sanctification.
- The Bondage of the Will — by Martin Luther. Discusses humanity’s inability apart from grace.
