Ephesians 3:5
5 Which in other ages was not made known unto the sons of men, as it is now revealed unto his holy apostles and prophets by the Spirit;
How could the mystery of Christ be hidden in previous ages and yet known by the OT Prophets?
PROBLEM: According to this passage, the mystery of the church, the body of Christ, was not known in other ages. Yet the apostle goes on to say that it was revealed to the “apostles and prophets.” But the prophets lived prior to the time of Paul. How could the prophets have known if people in the OT did not know the mystery?
SOLUTION: There are several reasons for believing that Paul is referring to NT prophets, not OT ones.
Second, this same phrase is used to describe the foundation of the NT church which is built on the “foundation of the apostles and prophets” (Ephesians 2:20). But the NT church did not begin in the OT, but only after Christ announced it in Matthew 16:18.
Third, the text says clearly that the mystery of the spiritual body of Christ “was not made known” to the sons of men “in other ages” but only now to “the apostles and prophets” (Ephesians 3:5).
Finally, the parallel passage in Colossians says emphatically, “the mystery … has been hidden from ages and from generations, but now has been revealed to His saints” (1:26). Thus, the “prophets” to whom it was made known were NT prophets (cf. 1 Corinthians 12:28; Ephesians 4:11).