The church in Thessalonica had come to Christ through the gospel message about Jesus, who rescues people from God's wrath. Paul and his team brought the gospel to the city. As people believed, their transformed lives and joy propelled the news about Jesus throughout the whole region. It was organic evangelism: good news spreading like wildfire as the seed of truth was being scattered widely by those who had received it.
 
This passage demonstrates the nature of true conversion. Firstly, it was all based on the apostolic gospel (there is no other true gospel – Galatians 1:6-9). Paul had been given Christ's direct commission to take the gospel to the Gentiles. Their willingness to receive both the message and its messengers showed that they were responding to the Word of God. Secondly, they made a radical decision to abandon their former religious life and stop worshipping idols. That choice invited opposition from friends and family, but also invited the opportunity to explain what they believed about Jesus.
 
Thirdly, they intentionally turned to serve the true God. Many people claimed to worship a god but the believers knew that God is defined as God the Father who raised God the Son from the dead. Fourthly, they had an eternal perspective. They understood that life on earth is only temporary; it will all come to an end when Jesus returns, and they were willing to serve Him faithfully until that day. Fifthly, they understood that their sins could only be washed away through the sacrifice of Jesus, so that they would be blameless when Jesus comes as Judge (1 Peter 4:5).
 
In a world where people believe many ideas, it is important to understand that God the Father is best known and understood by His relationship to Jesus Christ. His death is the only atoning sacrifice for sins and the only protection against the Father's wrath about our rebellion (1 John 4:10). Believing this apostolic gospel brings about true conversion: a change on the inside which expresses itself in turning from idols to serve the true God we cannot see but for whom we wait. When other people see that conversion, and ask questions, the answers given by the believers should stimulate more people to seek Jesus in order to find the true God. May the Lord enable you to be that kind of witness of the grace of Christ.