This letter was written around 60 AD when Paul was in jail in Rome. It is concerned first of all with “God's plan...to bring all creation together, everything in heaven and on earth, with Christ as head”. (1.10) It is also an appeal to God's people to live out the meaning of this great plan for the unity of the human race through oneness with Jesus Christ.
Several figures of speech are used to show the oneness of God's people in union with Christ: the church is like a body, with Christ as the head; or like a building, with Christ as the cornerstone; or like a wife, with Christ as the husband. This letter rises to great heights of expression as the writer is moved by the thought of God's grace in Christ. Everything is seen in the light of Christ's love, sacrifice, forgiveness, grace, and purity.