Writing from prison and having lived through some difficult circumstances, Paul was uniquely qualified to speak of finding strength in his joy in the Lord. When all hope seemed lost, Paul was found singing his prison cell or writing a letter to encourage other Jesus-followers. The conflicts outside the church and the conflicts inside the church provided an opportunity for some to lost hope. The joy of the Lord became Paul’s strength to live in harmony with other believers (4:2-3), rejoice in all circumstances (4:4-7), and develop an attractive reasonableness (4:8-9). His deep concern for this church in Philippi was that they remain firm in the Lord.