The first letter to the Thessalonians was likely the first of all Paul's letters, most like written by the end of A.D. 52. It was written after Timothy had returned from Macedonia, relating the state of the church in Thessalonica (Acts 18:1-5; 1 Thess. 3:6). While, on the whole, the report of Timothy was encouraging, it also showed that many errors and misunderstandings regarding Paul's teaching of Christianity had crept in among them. Paul addresses them in this letter in order to correct the church and exhorts the Thessalonians to purity of life, reminding them that their sanctification was God's will for their lives.

The second epistle to the Thessalonians was probably written from Corinth, Greece not many months after the first. Apparently the first letter was misunderstood, especially regarding the second advent of Christ. The Thessalonians had embraced the idea that Paul had taught that "the day of Christ was at hand", that Christ's coming was about to occur. This error is corrected (2:1-12), and the apostle announces what first must take place before the end times. The "Great Apostasy" is first mentioned here.