What does Philippians 1:3 mean?

Verse 3 begins the main body of the letter. Paul begins with thanks and encouragement. He had many reasons to be thankful for the Philippians. First, with their help, he had successfully founded a church in their city (Acts 16). Second, these believers faithfully supported his ministry over the previous years (Philippians 4:16). Not all of the churches Paul worked with were so generous (2 Corinthians 11:7–9).

Paul offered a similar opening of thanks in another Prison Epistle: "We always thank God, the Father of our Lord Jesus Christ, when we pray for you" (Colossians 1:3). Likely written in the same time period, and both including Timothy (Colossians 1:1), each letter includes an opening with encouraging words for readers. A third Prison Epistle, Philemon, is written to an individual, yet includes similar words of thankfulness: "I thank my God always when I remember you in my prayers" (Philemon 1:4), again including Timothy as a co–writer (Philemon 1:1).