Paul's letter talks about what the city was like regarding is faith. There was a lot of pagan activity there along with Judaism. Paul wrote this letter to thank those in Thessalonica for all they did and were doing as well their growing faith. They had written Paul with a variety of questions and he answered them in this letter.
His writing was to encourage them even in the midst of their trials and struggles. He responded to charges that his preaching and team were our for money, which they were not. He wrote to encourage the church to not be lazy and to keep moving forward in their work as believers.
In chapter one, Paul talks about how pleased and thankful he is for their salvation and he expresses his thanks to God for the work He has done in Thessalonica. He expresses how their present state gives him cause for joy. The Thessalonians eagerly received the message of salvation even during some hard times, which encouraged Paul. Happily he had witnessed the Thessalonian's choice to serve God, the one true God.
Chapter two record Paul's visit and he addresses the false accusations made against him by those who opposed him. Paul also instructs them to lead lives worthy of the choice they made and worthy of the Almighty God they served. We can learn from this instruction for all who have chosen to walk with God can learn from this.
Paul discusses the persecution of the Thessalonians and who it was who was after them. Paul has a deep understanding of persecuting Christians as he, himself did it with passion.
Chapter three tells of his concern for the church there as they were suffering greatly under persecution. He talks of sending Timoth to encourage them and to find out how they were holding up. He responding with joy that they were doing great and standing up to the troubles they were experiencing. He speaks of how grateful he was that they have been standing strong and thanks God for them. Paul ends three with a prayer that may reach to you from his time. I am sure that his prayer would be for all of you had he been living now. It might be a prayer we pray for each other as believers. We pray that the Lord would make our love for each other and all people grow to overflowing. We pray that our hearts would be strong, blameless and holy as we stand before God at that time when Jesus comes again. What a wonderful prayer to pray back then and even today. This instruction and encouragement carry on in chapter four.