A man in the Greek city of Philippi asked a very similar question of Paul and Silas. We know at least three things about this man: he was a jailer, he was a pagan, and he was desperate. He had been on the verge of suicide when Paul stopped him. And that’s when the man asked, “What must I do to be saved?” (Acts 16:30).
The very fact that the man asks the question shows that he recognized his need of salvation—he saw only death for himself, and he knew he needed help. The fact that he asks Paul and Silas shows that he believed they had the answer.
That answer comes swiftly and simply: “Believe on the Lord Jesus Christ, and you shall be saved” (verse 31). The passage goes on to show how the man did believe and was converted. His life began displaying the difference from that day forward.
Note that the man’s conversion was based on faith (“Believe”). He had to trust Jesus and nothing else. The man believed that Jesus was the Son of God (“Lord”) and the Messiah who fulfilled the scriptures (“Christ”). His faith also included a belief that Jesus died for sin and rose again, because that was the message that Paul and Silas were preaching (see Romans 10:9-10 and 1 Corinthians 15:1-4).
To “convert” is literally “to turn.” When we turn towards one thing, we by necessity turn away from something else. When we turn to Jesus, a turning from sin is implied. The Bible describes “repentance” as a change of mind about sin and a change of mind about Jesus, and then a turning to Jesus in “faith.” Therefore, repentance and faith are complementary. Both repentance and faith are indicated in 1 Thessalonians 1:9—“You turned to God from idols.” A Christian will leave behind his former ways and anything pertaining to false religion as the result of a genuine conversion to Christianity.
To put it simply, to convert to Christianity, you must believe that Jesus is the Son of God who died for your sin and rose again. You must agree with God that you are a sinner in need of salvation, and you must trust in Jesus alone to save you. When you do this, God promises to save you and give you the Holy Spirit, Who will make you a new creature.
Christianity, in its true form, is not a religion. Christianity, according to the Bible, is a relationship with Jesus Christ. Christianity is God offering salvation to anyone who believes and trusts the sacrifice of Jesus on the cross. A person who converts to Christianity is not leaving one religion for another religion. Converting to Christianity is receiving the gift that God offers and beginning a personal relationship with Jesus Christ that results in the forgiveness of sins and eternity in Heaven after death.