Which was not made known to the sons of men in other generations. Though not a new purpose, the knowledge of it is new. Abraham, David, and the prophets, however much they knew of Christ and the fullness of blessing in him for all the families of the earth, did not know the full extent of God's grace to the Gentries—did not know that the middle wall was to be wholly broken down, and all inequality removed.
This might seem to throw some doubt on the reality of this doctrine; but it was on purpose that God kept it secret, and those by whom he has now revealed it are worthy of all regard. As it has now been revealed unto his holy apostles and prophets in the Spirit.
It is not revealed to Paul only, although he has got the privilege of announcing it to the Gentiles, but to the whole body of "holy apostles and prophets." The designation, "holy apostles," is rare; it is used here to magnify the office, to show that those whom the Head of the Church had set apart for himself were fit instruments to receive so important a revelation.
"Prophets" here are undoubtedly New Testament prophets (see Ephesians 2:20), the contrast being with "sons of men in other generations." Reference may be made to the experience and decree of the Council of Jerusalem, guided by the Holy Spirit (see Acts 15:28).