1. The first letter was written to the struggling church mentioned in Acts 17:1–9.
2. Paul’s first letter was probably a response to a letter sent to him from Thessalonica (1 Thess. 4:9; 5:1, cf. 1 Cor. 7:1, 25; 8:1).
3. Apparently, some had accused Paul of fleeing when times got tough and so Paul defends his ministry in his first letter.
4. Thessalonica was a major port city and the most important city in Macedonia in the first century. Thus, Paul’s readers were likely from a large church comprised of people from many ethnicities and social classes. 
5. The main purpose of Paul’s second letter was to clarify his eschatological teachings and to encourage the church in the face of persecution.

In Thessalonians, God is glorifying Himself through the Thessalonian’s steadfastness, so that He might demonstrate His superior goodness in the salvation sinners, the damnation of the wicked, and for the preservation of His people, for His eternal glory, and their eternal joy.

“Paul, Silvanus, and Timothy…” 

1 Thessalonians 1:1; 2 Thessalonians 1:1

“Therefore we wanted to come to you—even I, Paul, time and again—but Satan hindered us” 

1 Thessalonians 2:18

“The salutation of Paul with my own hand, which is a sign in every epistle; so I write”

2 Thessalonians 3:17

“To the church of the Thessalonians in God the Father and the Lord Jesus Christ” 

1 Thessalonians 1:1–2, Thessalonians 1:1

“Your faith toward God has gone out, so that we do not need to say anything. For they themselves declare concerning us what manner of entry we had to you, and how you turned to God from idols to serve the living and true God, and to wait for His Son from heaven, whom He raised from the dead, even Jesus who delivers us from the wrath to come.”

1 Thessalonians 1:8–10

“But we are bound to give thanks to God always for you, brethren beloved by the Lord, because God from the beginning chose you for salvation through sanctification by the Spirit and belief in the truth, to which He called you by our gospel, for the obtaining of the glory of our Lord Jesus Christ. Therefore, brethren, stand fast and hold the traditions which you were taught, whether by word or our epistle.”

2 Thessalonians 2:13–15

“But we command you, brethren, in the name of our Lord Jesus Christ, that you withdraw from every brother who walks disorderly and not according to the tradition which he received from us. For you yourselves know how you ought to follow us, for we were not disorderly among you; nor did we eat anyone’s bread free of charge, but worked with labor and toil night and day, that we might not be a burden to any of you, not because we do not have authority, but to make ourselves an example of how you should follow us.”

2 Thessalonians 3:6–9

1. We do not need to sorrow without hope concerning those who have died, because we know that the dead in Christ will rise from the grave.
2. We ought to watch and be sober as we wait for the day of the Lord.
3. We should withdraw from every brother who walks disorderly.

1 Thessalonians

1. Paul’s Encouragement (1 Thess. 1–3)
2. Practical Exhortations (1 Thess. 4–5)

2 Thessalonians

1. The Coming Day of the Lord (2 Thess. 1)
2. The Revealing of the Son of Perdition (2 Thess. 2)
3. A Warning Against Idleness (2 Thess. 3)