What is important to you? What you want determines what brings you joy. In this section of Scripture Paul tells the Philippian believers that he thinks of them often and that their ministry together has cemented them in his heart. His prayers include requests for their spiritual maturity, discernment and for their blessing. The very thought of them brings him joy. Circumstances could not rob his joy, because he was not living for circumstances. Paul was living to serve the Lord Jesus Christ and he loved his fellow servants.
These verses remind us that we need to focus on what is important to us. If you are living for ease you will be disappointed. If you are living for perfect circumstances you will be disappointed. If you focus on the fellowship you can have with other believers and allow that relationship to drive your life purpose you can have joy.