The origin of the word proselyte is a Greek word meaning “stranger” or “newcomer.” At first, a proselyte was simply a convert to Judaism, usually from Greek paganism. Today, the word proselyte refers to a new convert to any religion or doctrine. Proselytization is the seeking of converts, and it is something Christians are commanded to do (Matthew 28:18–20).
Although Christians are commanded to proselytize, the Bible is clear that the conversion of the human heart is first and foremost an act of God. Before the disciples could evangelize the world, Jesus told them to wait in Jerusalem for the Holy Spirit to come (Luke 24:49). The making of a proselyte is more than just getting someone to agree to a set of doctrines. A true convert is someone who has been raised from death to life (Ephesians 2:1), born again (John 3:3), and rescued from the kingdom of darkness to be translated into the kingdom of righteousness (Colossians 1:13). The making of a proselyte is truly God’s work. It is “not by might nor by power, but by my Spirit, says the LORD Almighty” (Zechariah 4:6).
However, there is also a human element required in the process of proselytization. When Cornelius needed to be saved, God sent a human preacher (Peter) to share the gospel with him. “Peter opened his mouth” (Acts 10:34, ESV), and so must we. “How can they hear without someone preaching to them?” (Romans 10:14). It has pleased God “through the foolishness of what was preached to save those who believe” (1 Corinthians 1:21).
Christians believe in proselytization because we believe that the universal problem (sin) has a universal solution (Christ’s sacrifice). “All have sinned” (Romans 3:23) and are deserving of death. Yet Christ “was delivered over to death for our sins and was raised to life for our justification” (Romans 4:25). This is the gospel, the good news that must be shared with a needy world. We proselytize because we believe the need is urgent.
Christians attempt to proselytize all nations because Jesus desires all nations to hear and respond to the gospel (Luke 24:47). Jesus did not speak of conversion to a religious system, but He presented Himself as the liberty of the oppressed and a sign of the Lord’s favor (Luke 4:18–19). In regards to the nations, God says He will change the speech of the peoples to a pure speech, so that they may call upon the name of the Lord and serve Him (Zephaniah 3:9). This prophecy of Zephaniah refers to the eventual conversion of the believing from all nations, showing that God loves and calls people of all races, nationalities, and creeds to be His own. The prophecy goes on to say that the people will seek refuge in God’s name, and there will be no more lying and no more fear.
Christians believe in proselytization because we believe in this refuge of God, and we want all people to come to Him and enjoy His rest and peace and love. It is a joyful thing for a Christian—perhaps the most joyful thing—to know that those we know and love are safe in Him (Acts 15:3). Christians engage in witnessing, sharing the gospel, and speaking the truth (all considered proselytization) for the sake of that joy. We are compelled by the Holy Spirit to speak, and those who convert are also drawn by Him. That is one difference between Christianity and other religions. A true proselyte to Christianity is drawn by God Himself, not manipulated into conversion by human means (John 6:44).