This book provides a touching glimpse of Paul as a pastor. Paul visited Thessalonica at a troubled times in his history, while enemies were tailing him from town to town (see Acts 16-17). After he left, the church continued to meet hostility.
First Thessalonians is our earliest record of the life of a Christian community. Paul wrote this letter after receving a mostly positive report (from Timothy) on the Thessalonians' spiritual health. He rejoiced at the good news, but also showed concern over the church's problems.
As you read 1 Thessalonians, notice the issues that Paul addresses: Christians were raising questions about Jesus' return to earth and were disagreeing on matters of morality. But mainly, look for signs of Paul's relationship to the church at Thessalonica.