Few doctrines are as important for the missionary as the doctrine of conversion.
How you define conversion and how you think it happens will impact your missiology and practice on every level. In a world where we are tempted by every blowing wind of doctrinal change, we need to anchor ourselves to the biblical doctrine of conversion before we engage in world missions.
A Simple Definition
The simplest definition of conversion is “to turn to God.” In most English Bibles (KJV, ESV, NIV, NASB, NRSV, CSB, etc.) the only place you will find the English word “conversion” is in Acts 15:3.
So, being sent on their way by the church, they passed through both Phoenicia and Samaria, describing in detail the conversion of the Gentiles, and brought great joy to all the brothers (Acts 15:3).
The underlying Greek word here is the noun epistrophe. It means “to turn or change one’s way of thinking.” Other passages in the New Testament use the corresponding verb epistrephō, which, depending on the context, refers to ideas in the range of “to turn, go back, return, to change one’s mind, or change belief and conduct.” It can be used in a directional context, as when you are traveling one way and turn around to go back (Matthew 12:44; Mark 13:16; Luke 2:39); a simple turning around of your body to face a new direction (Mark 5:30; John 21:20; Acts 9:40); or turning to the Lord to follow him (Mark 4:12; Luke 1:16; Acts 3:19; 9:35; 11:21; 14:15; 15:19, etc.). It is these latter uses that concern us when we think about the doctrine of conversion.
Turning From Idolatry in the Old Testament
The doctrine of conversion is rooted in the Old Testament; it is not merely a New Testament concept. Scripture regularly shows that people need to turn to God.
One of the consistent themes in the Old Testament, particularly in the prophets, is that Israel has fallen into apostasy by abandoning God for the idols of the nations. As early as the golden calf incident at Mt. Sinai, we see Israel’s propensity—the human propensity—to turn away from God and create idols. Israel has turned aside and departed from the Lord (Hebrew sûr; Exodus 32:8; Deuteronomy 9:12,16; Judges 2:17; Jeremiah 5:23; Daniel 9:11; Malachai 2:8; 3:7) and needs to turn back (Hebrew šwb). This turn is repentance. Israel is warned over and over not to turn aside (Deuteronomy 11:28; 28:14; 1 Samuel 12:20). She is called over and over to return, repent, and forsake idols (Joshua 24:23; 1 Samuel 7:3; 2 Chronicles 30:6-9; Isaiah 31:6; 30:15; 55:7; Jeremiah 3:12-14, 18-22; 4:1-2; 35:15; Ezekiel 14:6; 18:30; Hosea 6:1; 12:6; 14:1; Joel 2:12-13; Zechariah 1:3; Malachai 3:7; et al). Yet like all humans in their sin, she is a stiff-necked people (Exodus 32:9; 33:3,5; 2 Chronicles 30:8; Acts 7:51; similarly Jeremiah 7:24; 11:8) and her heart needs a spiritual circumcision (Deuteronomy 10:16; Jeremiah 4:4; 9:26; Acts 7:51).
One of the most important elements of the Old Testament storyline is that God will bring his people back to himself despite their rebellion. As in the Book of Hosea, she is the cheating spouse, but God is the faithful bridegroom. Given the story of the golden calf, it does not take much imagination to realize Israel would again go astray (Deuteronomy 31:29). Moses prophesies, inspired by the Holy Spirit, that she will break the covenant, and the curse of the covenant will leave her exiled from her land—a symbolic divorce, as she is cut off (Deuteronomy 4:25-30; 28:58-65; 29:20-28; 30:1). But God will not forget his covenant with Abraham (Deuteronomy 4:31; Leviticus 26:42). Deuteronomy 30:1-6 gives us this hope:
“And when all these things come upon you, the blessing and the curse, which I have set before you, and you call them to mind among all the nations where the LORD your God has driven you, and return to the LORD your God, you and your children, and obey his voice in all that I command you today, with all your heart and with all your soul, then the LORD your God will restore your fortunes and have mercy on you, and he will gather you again from all the peoples where the LORD your God has scattered you. If your outcasts are in the uttermost parts of heaven, from there the LORD your God will gather you, and from there he will take you. And the LORD your God will bring you into the land that your fathers possessed, that you may possess it. And he will make you more prosperous and numerous than your fathers. And the LORD your God will circumcise your heart and the heart of your offspring, so that you will love the LORD your God with all your heart and with all your soul, that you may live.[”]
This is the foundation for the promise of the New Covenant. It is why Daniel reads the promise of Jeremiah (Jeremiah 25:12) and, at the end of 70 years in exile, turns and prays the prayer of repentance on behalf of his people (Daniel 9). It is why John the Baptist, the last of the prophets, brings a baptism of repentance to prepare for the Lord’s coming (Mark 1:15). The great hope of God’s people is that God will give them a new heart, a converted heart, that is fundamentally different at its core (Jeremiah 31:31-34; 32:36-41; Ezekiel 11:14-19; 36:22-27). It is not enough that we turn to God, but God must act upon us and change us from what we were to make us new, empowering us to walk in his ways. Through this conversion, God’s people will come to truly know God, walking in intimate covenant fellowship in contrast to the countless times they have previously forsaken him (Jeremiah 31:40; Ezekiel 36:27-29).
Preaching and Conversion in Acts
Whenever the gospel is preached in the book of Acts, the speaker announces the death, resurrection, and ascension of Jesus Christ and calls people to believe and repent. Conversion happens when the people turn to God and his Messiah in faith and receive the forgiveness of sin.
In the first chapters of Acts, the gospel is preached to Jewish people first in Jerusalem and then in the surrounding towns. At Pentecost, the Holy Spirit is poured out upon believers in fulfillment of Joel 2:28-32, a clear sign that the New Covenant was inaugurated as Christ became the covenant sacrifice for the removal of sin (Luke 22:20; Hebrews 9:15). Peter proclaims the good news that Jesus has been made Lord and Messiah in his exaltation (Acts 2:22-26) and then calls the people to repent and be baptized in the name of Jesus Christ. Similarly, in Acts 3:19, Peter again calls his brothers to repent, turn again, and receive the forgiveness of sin.
In this respect, Peter is not calling his fellow Jews to join a new religion but to understand that what God has done in Jesus is the fulfillment of the promises of the Old Testament. God raised up his promised servant, the son of David, a prophet like Moses (Acts 3:22-26). The days of the coming servant when Israel must return and repent are now at hand (Acts 3:24). God made a covenant with Abraham, and he is keeping it (Acts 3:25). God has acted to turn them from their wickedness (Acts 3:26). While Israel had the law, in her uncircumcised heart, she did not keep it (Acts 7:51-53). Their great need is to repent and turn, to put their faith in Christ and experience the promised circumcision of the heart. While many in these Jewish audiences knew about the God of Abraham and his many covenant promises and works of redemption, they still needed to come to know God—to enter into the relationship with him that comes only through Jesus Christ (Acts 4:12).
From Jerusalem, the gospel continues to spread outward geographically as the regions of Judah and Samaria begin to be reached (Acts 8:1, 14). In Acts 11:19, we find the disciples in Phoenicia, Cyprus, and Antioch. There, the Lord Jesus was proclaimed to Hellenistic Jews, and they turned (epistrephō) to the Lord in great number (11:20-21).
Soon the gospel spreads to Gentiles around the Roman Empire, and the church sends out Paul and Barnabas (Acts 13:1-3). In Lystra, Paul and Barnabas are praised as gods when they heal a crippled man. They zealously cry out against such blasphemy, saying instead, “we bring you good news, that you should turn from these vain things to a living God” (Acts 14:15). Proclaiming the gospel brings the call of conversion: to turn from idolatry to the true and living God. It is a way of saying, “You are walking in sin and rebellion; be converted.”
Many Gentiles did turn from their idolatry and believe in the living God and his Son, the Lord Jesus Christ. This brings us again to Acts 15, when the early church wrestled theologically with the reality of Gentile salvation. Could those outside of Abraham’s circumcision receive the blessings promised to Israel’s forefathers? If Abraham turned from his family idols to the living God, shouldn’t Gentiles who have turned also get circumcised? Here we are reminded that the promise to Abraham was that all the nations would be blessed in him (Genesis 12:3; cf. Acts 3:25), a reality that surely comes to pass through their faith in Christ (Galatians 3:7-9, 14, 27-29). These Gentiles have converted, having turned to the true God (Acts 15:3, 19). God is taking a people for his name from among the nations (Acts 15:14) as they call on his name and are saved (Acts 15:17; Romans 10:11-13).
We Turn Because God Turns Our Hearts
One more verse from Acts is worth pointing to in our discussion of conversion, namely Acts 26:18. In this verse, Paul recounts his apostolic commission to the Gentiles that he received from the Lord during his Damascus Road conversion:
I am sending you to open their eyes, so that they may turn from darkness to light and from the power of Satan to God, that they may receive forgiveness of sins and a place among those who are sanctified by faith in me.
Only God can change the heart. Before a person can turn from darkness to light, the eyes of their heart must be opened. The Lord is the one who opens the heart, but he uses the preaching of the Word to do so. Faith comes through hearing (Romans 10:17). Therefore, for someone to be saved, a believer has to go and preach the gospel (Romans 10:14), and God uses that preaching of his Word to open the eyes of the blind.
We might put this another way: there is a subjective experience in which we turn and cry out to God. We believe and repent (actions which are really two sides of the same coin). But the reason we do that is because God is using the preaching of his Word to cause the light of the gospel to shine in our hearts. God acts. We respond.
Paul, in a passage that echoes his own conversion call, outlines this basic reality. Just as a cry from heaven opened the eyes of his heart while he was walking on the Damascus Road, the Holy Spirit, through gospel proclamation, opens the eyes of our hearts so we may grasp Christ with saving faith.
Therefore, having this ministry by the mercy of God, we do not lose heart. But we have renounced disgraceful, underhanded ways. We refuse to practice cunning or to tamper with God’s word, but by the open statement of the truth we would commend ourselves to everyone’s conscience in the sight of God. And even if our gospel is veiled, it is veiled to those who are perishing. In their case the god of this world has blinded the minds of the unbelievers, to keep them from seeing the light of the gospel of the glory of Christ, who is the image of God. For what we proclaim is not ourselves, but Jesus Christ as Lord, with ourselves as your servants for Jesus’ sake. For God, who said, “Let light shine out of darkness,” has shone in our hearts to give the light of the knowledge of the glory of God in the face of Jesus Christ. (2 Corinthians 4:1-6)
We turn from darkness to light because God, the sovereign Creator, declares the light to shine in our hearts. Just as the original creation was formed ex nihilo, so too there is no light in our hearts until God calls it into existence within us. Put another way, we are dead in our sins and transgressions (Ephesians 2:1-3), but God, being rich in mercy, makes us alive (Ephesians 2:4). Just as God alone raises the dead, so God alone saves the sinner. He does the work; we are mere servants in preaching the gospel, which is why we don’t twist or tamper with it. God will use the “foolish preaching” (at least foolish in the world’s eyes) of Christ’s crucifixion to use his resurrection power to raise up the sinner’s dead heart and grant them life (1 Corinthians 1:18). This is conversion: God breathes life; we are changed; we turn to God.
Conversion: Out With the Old, In With the New
In our conversion, the old man—the self that was dead in sin—is crucified and put to death in the death of Christ (Romans 6:5). Christ’s death on Golgotha is applied experientially to me so that I am changed. Just like he died and rose again, inside me I have spiritually died in his death and been raised to walk in a new life (Romans 6:3-4, 11, 22). At the core of my being, everything has changed. While sin is still present in my body, I am fundamentally a new creation (2 Corinthians 5:17). The promised Holy Spirit of the New Covenant is now inside me (Romans 8:1-4, 9-11; 2 Corinthians 3:6, 16-18; Hebrews 9:14-15).
The Thessalonian church powerfully evidenced this transformation when they turned from idolatry: “For they themselves report concerning us the kind of reception we had among you, and how you turned to God from idols to serve the living and true God” (1 Thessalonians 1:9). To turn to God also means to turn away from all those things which are not God.
Similar examples of this transformation multiply through Scripture. In Acts 19:19, those who turned to Christ burned the books of their magic arts. In proclaiming the gospel, Paul was also calling the lost to turn away from the things that are not gods (Acts 19:26). The silversmith guild quickly realized this would eviscerate their profit from making idols (Acts 19:23-41), and a riot broke out in Ephesus.
In 1 Peter, we find reminders that the unsaved once walked in the passions of the world and in darkness until God called them out (1 Peter 1:14; 2:9-12). The Corinthians are exhorted not to fall into idolatry like the people of God did in the Old Testament (1 Corinthians 10:1-11). They must not participate in “the cup of demons” because they are the Lord’s and partake of his table (1 Corinthians 10:14-22; cf. Acts 15:29). Turning to God means turning away from idols.
The proclamation of the gospel is a call to idolaters and those far from God to turn, repent, and receive the forgiveness of sins offered in Jesus Christ. When Paul saw the rampant idolatry in Athens, his spirit was provoked and a flame fanned within him to boldly call out their ignorant rebellion:
Being then God’s offspring, we ought not to think that the divine being is like gold or silver or stone, an image formed by the art and imagination of man. The times of ignorance God overlooked, but now he commands all people everywhere to repent, because he has fixed a day on which he will judge the world in righteousness by a man whom he has appointed; and of this he has given assurance to all by raising him from the dead. (Acts 17:29-31).
Implications for Missions
A strong doctrine of conversion will have deep implications for our engagement in missions, particularly as we consider our means and methods.
1. God is spreading the good news of the gospel, saving people who did not know him, and making them his people.
The salvation of the lost is the work of God. God alone saves. And God is rich in mercy and grace, bringing people from every tongue, every tribe, and every nation to worship him (Revelation 5:9-10). He is the God of both Jews and Gentiles (Romans 3:29; 10:11-13).
2. Faith comes through hearing.
If God alone saves, then we need to pay close attention to how God saves the lost. Of course, the ultimate foundation of salvation is the death and resurrection of Christ. But the means by which a sinner comes to receive it is through the proclamation of the Word. Gimmicks, laser light shows, puppets, mimes, and fog machines don’t save people. God saves people through the proclamation of his Word. “So faith comes from hearing, and hearing through the word of Christ” (Romans 10:17). Therefore, the missionary must zealously and faithfully communicate the gospel, and the only way to communicate it is to use words. News is never communicated without words; the good news must likewise be spoken, heralded, and proclaimed.
3. Messengers must be sent.
The Great Commission is to go, make disciples, and teach. But people will not believe the gospel if they’ve never heard the gospel, and for them to hear it, someone has to preach it (Romans 10:14). Thus, proclaimers must be sent (Romans 10:15). We are not called to climb up to our highest steeples and just shout the Word; instead, we are called to walk into the places around the world where others have not heard about it. We go, take the message, and tell them. When messengers are sent, and those messengers proclaim, people will believe the message and turn to God. God will bring conversion.
4. If we want to multiply converts, we should multiply the ministry of the Word.
By now, it should be obvious that we don’t make converts; that is God’s work. We spread the seed of God’s Word by planting and watering, but God brings the growth (1 Corinthians 3:6-9). If we want to see disciples multiplied, we should focus on the task God has given us, namely spreading the gospel. In Acts, when the Word was increasingly ministered, disciples multiplied (Acts 4:4; 6:7; 12:24; 13:48-49; 20:32). Today, evangelicals need to return to this rock-solid confidence in the Word of God. We need to quit tampering with it and trust that God will do the work through his Word.
5. Come out from idolatry and gather as the church.
In many places around the world, this is easier said than done. Nevertheless, even in the most closed countries, where believers must gather in secret, sharing the word of the gospel should lead to the formation of churches. When a person turns to the Lord, he or she is equally turning from idolatry. In the New Testament, there is no conception of converts who remain inside their systems of false religion and co-mingle with idolatry and false gods. Just as the converted magicians in Ephesus burned their books, or the Thessalonians turned from their idols, so today converts are called to walk out of their temple, mosque, kingdom hall, or alternate religion and worship God’s way. We should have the utmost care and compassion for what this will cost many of our brothers and sisters who live in societies deeply hostile to the living and true God. Nevertheless, the consistent pattern in the Old and New Testaments shows that to turn to God is to turn from idolatry and other religious systems. A new heart will bring a new allegiance. If Jesus is the Lord, the idols are not.
The church today wobbles in its doctrine of conversion like Jello on a plate. In some circles, adhering to a doctrine of conversion is deemed harsh and offensive. We settle for inviting people to make Jesus one more piece in the smorgasbord of their life without ever calling them to turn and repent. In other places, we long for the great revivals of old, but we figure that the best way to initiate them is to try new angles and methods—the things that for Paul amounted to tampering with God’s Word or gussying up the gospel with man-centered wisdom (2 Corinthians 4:2; cf. 1 Corinthians 2:1-5). We bait people with gimmicks and tricks, assuming that we can sneak in the gospel and they’ll barely notice. We don’t want to offend them. But why are we surprised when they don’t actually notice the gospel and its announcement that Jesus Christ is Lord? We need more direct statements of the truth, spoken with a confidence that God will convert the lost as he sees fit. In still other circles, we assume that all we need to do is love people, and by some spiritual kind of osmosis they’ll discern the deeper reason for our love is the death and resurrection of Jesus Christ, which they personally need to receive and believe.
It is time to return to the Scriptures. We must recover the robust theology of conversion contained therein. This doctrine must not only appear in our statements of faith but it needs to become a driving conviction that fuels our missionary zeal. It is time that we turn to God, forsake our evangelical idols, and trust that he converts the lost.
