Paul is the main author
The letter opens by naming Paul, Silvanus, and Timotheus as its senders to the church in Thessalonica (1 Thessalonians 1:1). Silvanus is the Latin form of Silas, and Timotheus is Timothy. They were close co-workers in the mission.
Still, 1 Thessalonians has long been recognised as a letter from Paul. He writes as the missionary who first brought the good news to this church, sharing his own longing to return and his personal anxiety for their faith (1 Thessalonians 2:18; 1 Thessalonians 3:5). The repeated use of “we” reflects a shared ministry team, not uncertainty about Paul’s leading role.
Paul, and Silvanus, and Timothy, unto the church of the Thessalonians which is in God the Father and in the Lord Jesus Christ: Grace be unto you, and peace, from God our Father, and the Lord Jesus Christ.
Who was Paul?
Paul had not always followed Jesus. Earlier in life, he was known as Saul and fiercely opposed the first Christians. On the road to Damascus, the risen Jesus confronted him and changed the direction of his life (Acts 9:3-6).
Paul then became a travelling messenger of Christ. He helped begin churches across the Roman world and wrote letters to guide, correct, comfort, and encourage them. His message centred on Jesus, who gave himself to deliver people from sin and bring them into a new life with God (Galatians 1:4).
Paul, an apostle, (not of men, neither by man, but by Jesus Christ, and God the Father, who raised him from the dead;)
Paul's connection with Thessalonica
Paul and Silas first preached in Thessalonica during a journey through Macedonia. Some Jews, devout Greeks, and prominent women believed the message, but others stirred up opposition in the city (Acts 17:1-5).
The situation became dangerous enough that fellow believers sent Paul and Silas away by night to Berea (Acts 17:10). That quick departure helps explain the warmth of 1 Thessalonians. Paul had not forgotten these new Christians. He wanted to know whether they were holding on to faith amid pressure.
And the brethren immediately sent away Paul and Silas by night unto Berea: who coming thither went into the synagogue of the Jews.
Why Paul wrote the letter
Paul sent Timothy to strengthen the Thessalonian believers and learn how they were doing (1 Thessalonians 3:2). When Timothy returned with good news about their faith and love, Paul responded with gratitude and relief (1 Thessalonians 3:6-8).
So this letter is personal as well as practical. Paul thanks God for them, urges them to live in ways that please God, and gives hope about Jesus' return. His tone is tender. He remembers working so he would not be a burden, caring for them like a parent cares for children (1 Thessalonians 2:9-12).
Reading 1 Thessalonians with Paul in mind helps its warmth come alive. This is a letter from a church planter who loved a young congregation and wanted them to keep trusting Christ.
But now when Timothy came from you unto us, and brought us good tidings of your faith and charity, and that ye have good remembrance of us always, desiring greatly to see us, as we also to see you: Therefore, brethren, we were comforted over you in all our affliction and distress by your faith: For now we live, if ye stand fast in the Lord.