Another note pertaining to ongoing discussions.
It may seem like a small matter, but is perhaps significant that the apostolic salutation in Romans 1: 7 (and elsewhere in Paul’s letters) is “grace and peace” (χάρις καὶ εἰρήνη). For with such an expression the Apostle Paul appropriates and enriches the common greetings of both Greeks and Hebrews. W. Sanday and A.C. Headlam comment:
Observe the combination and deepened religious significance of the common Greek salutation χαίρειν, and the common Heb. salutation Shalom, ‘Peace.’ χάρις and εἰρήνη are both used in the full theological sense: χάρις = the favour of God, εἰρήνη = the cessation of hostility to him and the peace of mind which follows upon it.
It is suggestive that this particular greeting is unique to Paul in the NT–Paul, a Jew, but one who spoke on the Areopagus and quoted Greek poets as the apostle to the Gentiles. Paul did not find it necessary to invent a new, uniquely Christian salutation out of whole cloth, nor did he find it necessary to use only the language of the Old Testament. He rather takes up elements of the Greek and Hebrew worlds both, and transforms them with Christian significance. He gives to the Greeks, previously feeling in the dark for its proper sense (cf. Acts 17:27), as it were, the true meaning of their χαίρειν, to the Jews the true meaning of their shalom, previously promised but only now fulfilled.