The Christians in Thessalonica were under fire from all directions. The unbelievers outside were still persecuting them. The unbelievers of the city had come after Paul when he first founded the church in this city (Acts 17:4–5), and they continued to afflict the church. Paul had (1s Thessalonians) and now writes to encourage them about this: the church had to continue growing in faith and love with the hope that Jesus would return.