How that, by revelation, was made known unto me the mystery. The mystery, as is explained afterwards (Ephesians 3:6), was not the gospel itself, but its destination to the Gentiles as much as to the Jews; although, as appears afterwards, this fullness of blessing is really the great glory of the gospel.
Mystery, that which is known only to the initiated, does not denote here a thing obscure in its own nature, but only something that had been concealed from view. It was only the initiated that now knew that God designed the gospel for Gentile and Jew alike.
Paul had been initiated "by revelation"—not by his own reflecting power, not by his study of Scripture, not by communication from ether men, but by a special communication from God (Galatians 1:12). As I wrote before in few words.
Where? In another Epistle? No; but in the earlier part of this Epistle (see Ephesians 1:9; Ephesians 2:18, etc.). If it be said the allusions in these places to the topic in question are rather vague and general, the apostle virtually admits it—he wrote of it "in few words;" but, as it is a great and glorious truth, he returns to it to amplify it and place it in a brighter light.