Sigurd Grindheim, «What the OT Prophets Did Not Know: The Mystery of the Church in Eph 3,2-13», Vol. 84 (2003) 531-553
The purpose of this essay is two-fold. First, it argues that the inclusion of the Gentiles is referred to as a previously unrevealed mystery because it is based upon the abrogation of the Mosaic law and entails a degree of nearness to the Lord that exceeds the expectations of the old covenant. Second, it addresses the question of authorship. Assuming Pauline authorship as a working hypothesis, it shows that the use of the concept of mystery in Eph 3 is intimately linked with Paul’s terminology and thought world attested in the undisputed letters. It is unwarranted, therefore, to find proof of a post-Pauline development in the use of the term "mystery" in Ephesians.
pronoun, au)tou, after "apostles" is an indication that Paul intends here a reference to two different groups, as the two terms clearly are being used to refer to different groups in Eph 4,1131. As one of the antitheses in v. 5 is between "previous generations" and "now", the prophets in view must be the New Testament prophets.
Paul himself is given a special insight into the mystery (v. 4, cf. vv. 18.104.22.168). In typical Pauline fashion, the passage Eph 3,1-11 juxtaposes two kinds of status. Vv. 2-7 are marked off with an inclusio with "grace" (th=j xa/ritoj tou= qeou= th=j doqei/shj moi in v. 2, and th_n dwrea_n th=j xa/ritoj tou= qeou= th=j doqei/shj moi in v. 7)32. "Grace" here refers to the ministerial grace33 and as such it is juxtaposed with Paul’s visible status. He is a prisoner (v. 1) and the least of the saints (v. 8). The same principle of revelation of the mystery is reflected here as in 1 Cor 2,6-16; God’s revelation turns the values of this world