What is conversion? When you hear the word “conversion,” you might think of an animated evangelist under a tent bellowing about being born again as a tearful man walks a sawdust aisle to the front. Or maybe you think about repeating a prayer at a youth conference or camp or someone leading someone else through the so-called “sinner’s prayer.” Or maybe you think about some other sensational or mountain top experience.
I’ve been to tent revivals, youth conferences, and charismatic worship services. I’ve had evangelism training. And in my experience, many Christians seem to think conversion is simply a one-time event, usually a sensational event, often linked to repeating a prayer and walking an aisle, and often not linked to membership and discipleship in a local church and ongoing growth in godliness.
We should think about conversion in at least two distinct but inseparable ways. Conversion is God making a dead sinner alive in Christ. Conversion is also God conforming His people to His Son. Conversion continues from the point of new birth on throughout the sinner’s life as the sinner is conformed more and more to Christ. To think of conversion in these two distinct but inseparable ways will help guard you against a false sense of assurance, “easy believism,” antinomianism, laziness in godliness, and discouragement while God completes His work of grace in you.
In his essay titled “Conversion,” Dr. R. Scott Clark explains, “Conversion begins with the gracious gift of new life and gives rise to a genuine faith and repentance that continue throughout the Christian life.”  Think about that. One, conversion is God graciously giving new life to a sinner. God makes them alive and grants them true faith and repentance. Two, conversion continues throughout the Christian life. This second aspect of conversion is what many Christians seem to miss or ignore or reject. Conversion is best understood as both initial and ongoing change by the grace and Spirit of God.
Ezekiel 36:25-27 is a great explanation of conversion. God says, “I will give you a new heart, and a new spirit I will put within you.” God also says, “and cause you to walk in my statutes and be careful to obey my rules.” Do you understand? Increasing carefulness to obey God is part of conversion.
Jesus discussed conversion with Nicodemus in John 3. Jesus said, “unless one is born again he cannot see the kingdom of God” (Jn. 3:3). Jesus explained that this new birth is worked by the Spirit (Jn. 3:5-6, 8). John returns to this theme in his first epistle and used the phrase “born of God” several times (1 Jn. 3:9; 4:7; 5:1, 4, 18). In 1 Peter 1:3, Peter explained that God “has caused us to be born again to a living hope through the resurrection of Jesus Christ from the dead.”
Paul wrote in 2 Corinthians 5:17, “Therefore, if anyone is in Christ, he is a new creation. The old has passed away; behold, the new has come.” Paul said, “is a new creation . . . has passed away . . . the new has come.” In one sense, conversion has happened. In Ephesians 2, Paul also wrote, “made us alive together with Christ” and “raised us up with him.” It’s been done. In Colossians 2:13–14, Paul wrote, “And you, who were dead in your trespasses and the uncircumcision of your flesh, God made alive together with him.” All this seems to be the first aspect of conversion. It is the initial change from death to life. By His sovereign grace, God takes dead sinners and makes them alive in Christ. There is a point where they pass from death to life, from darkness to light (Jn. 5:24; Rom. 6:13; Col. 1:13).
If we’re referring to conversion in a limited sense, as in the new birth, then conversion is a one-time event. However, conversion is bigger. Conversion includes the ongoing process of being conformed to Christ’s image. Many Christians seem to miss that conversion includes a process of change that continues throughout the Christian life. I think it’s true that many evangelistic events have confused people and led them to believe that repeating a prayer after a speaker and walking up front is conversion or at least evidence of conversion. It would be much better to think about conversion as necessarily including a definitive change and a life-long journey of putting sin to death and walking more and more in obedience to God’s law. Sadly, many hypocrites have a false sense of assurance because their idea of conversion is unbiblical, flawed, and incomplete.
True conversion is certainly being born again by the Holy Spirit. It’s receiving a new heart from God. But conversion is also a lifestyle of faith and repentance. Conversion is continual repentance from sin and pursuit of righteousness by grace alone through faith alone in Christ alone. Dr. Clark said:
Thus, repentance is an essential aspect of the beginning of the Christian life and also its ongoing development. In short, insofar as conversion encompasses turning and repentance, it is a lifelong process. 
In one sense, conversion is a definitive point where God makes the man dead in sin alive in Christ (the time of this conversion is not always discerned as in the case of an infant). In another sense, conversion is an ongoing process throughout the Christian life. Dr. Clark is right to say, “In short, the Christian life is a life of being converted daily.” 
Heidelberg 88 asks, “What is the true repentance or conversion of man?” It answers, “It is the dying of the old nature and the coming to life of the new.” Read Romans 6:1-11, Ephesians 4:22-24, and Colossians 3:5-17. They are very helpful in understanding the wholeness of conversion. Though we are dead to sin and alive in Christ, dear saints, we must continue to put our old man to death and put on Christ.
Heidelberg 89 asks, “What is the dying of the old nature?” It answers, “It is to grieve with heartfelt sorrow that we have offended God by our sin and more and more to hate it and flee from it.” Notice that part of conversion or true repentance is grieving over the fact that our sin offends our God and growing to hate and flee sin more and more. The “more and more” suggests growth, increase, and maturity. We are dead to sin (Rom. 6:11), but we are not done dying (Col. 3:5). We have made a definitive turn from sin (Rom. 6:2; 1 Thess. 1:9), but we must continue to flee sin (1 Cor. 6:18; 10:14; 1 Tim. 6:11).
And Heidelberg 90 explains what the coming to life of the new nature is. And isn’t this coming to life something that continues to happen? Heidelberg 90 states: “What is the coming to life of the new nature? It is a heartfelt joy in God through Christ and a love and delight to live according to the will of God in all good works.” Our joy in God is growing as the Spirit works. Our love and delight to obey our heavenly Father are growing as the Spirit works. We are doing good works as the Spirit works. This is conversion. This is sanctification.
In contrast to the Modern revival traditions we should better think of conversion as beginning with the gracious gift of new life (John 3:1–12) that gives rise to a genuine faith and repentance that continue throughout the Christian life as the believer trusts the Lord, lives in union with risen Christ, in the visible church, attending to the preaching of the Word, prayer, making use of the sacraments, and seeking to be brought into conformity daily with the Savior by the gracious renewing work of the Holy Spirit. 
Quotes from the Heidelberg Catechism and creeds are taken from Zacharias Ursinus & Jonathan Shirk, The Heidelberg Catechism: True Comfort for Life & Death (Manheim: Small Town Theologian, 2021), 395.
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