How can Paul rejoice when hes got nothing to rejoice about? How can he talk about joy when hes in prison? This book follows Paul as he writes to his friends in Philippi, helping us to understand his experience of joy as a totally consuming emotion. Paul highlights four reasons why joy fills his heart: because of the Gospel partnership he shares with his friends in Philippi; because of the unity that they experience in Christ; because of their confidence in Jesus; and because God has given them peace beyond understanding. These themes correspond with the four chapters of the letter, and form the organizing principle of this book.