The words "grace and peace" appear in the opening greeting of every Pauline letter. The romantic interpretation that they are a Christian synthesis of the pagan chairein 'rejoice' and the Jewish shalom 'peace' is unlikely to be correct, because in his second letter Paul feels the need to to give them an explicitly Christian dimension by the addition of "from God the Father and the Lord Jesus Christ" (2 Thess 1:2). This makes the phrase evocative of the Israelite blessing, "May the Lord bless you and keep you. May the Lord make his face shine upon you and may he be gracious to you. May the Lord show you his face and give you peace" (Num 6:24-26).

If God is the source of grace, it cannot be a mere benign regard, as the translation 'favour' might suggest, but must be a positive display of divine power, which is better rendered by 'benefaction'. It enables something that is impossible for fallen human nature. 'Peace' is important to Paul because it was the antithesis of the world in which he worked. Texts such as Gal 3:28 show that he believed that society was characterized above all by divisions. Individuals and groups isolated themselves by barriers of fear and suspicion. Thus the basic mission of the church was to demonstrate the reality of "You (plural) are all one person in Christ Jesus" (Gal 3:28). This could be true, however, only when the members of the church were at peace with one another. Such peace was the work of grace.

- Jerome Murphy-O'Connor, OP