Has been hidden (613) (apokrupto form apó = from, away + krúpto = hide, conceal by covering) means to hide away from the common gaze, and therefore secret. Apokrupto is used by Paul here (and 1Cor 2:7, Col 1:26) in a figurative sense to describe knowledge that cannot be known except through divine revelation. It is used in secular Greek writings of a "hidden trade (craft or skill)". Paul uses the perfect tense which emphasizes the longevity of the hiding of the mystery of the Church. Once again Paul is pointing out the fact that the church universal is something new, unique, unprecedented and was not known before to anyone but God. It was certainly not known in the OT, which is significant in that many commentators interpret the OT passages given to Israel as if they were given to the church. While the OT Scriptures have many applications, including application to the NT church and NT believers, there is only one valid literal interpretation and that interpretation relates to the nation of Israel and not to the NT church (see the related topic - Israel of God - Is God "Finished" with Israel in His prophetic plan?) Apokrupto - 4x in 4v in the NT - Luke 10:21 At that very time He rejoiced greatly in the Holy Spirit, and said, "I praise Thee, O Father, Lord of heaven and earth, that Thou didst hide these things from the wise and intelligent and didst reveal them to babes. Yes, Father, for thus it was well-pleasing in Thy sight. 1Corinthians 2:7 but we speak God's wisdom in a mystery, the hidden wisdom, which God predestined before the ages to our glory; Ephesians 3:9 and to bring to light what is the administration of the mystery which for ages has been hidden in God, who created all things; Colossians 1:26-note that is, the mystery which has been hidden from the past ages and generations; but has now been manifested to His saints (What is the mystery in this case? Col 1:27 = Christ in you, the hope or absolute certainty of future glory!) Apokrupto is found 8x in the Septuagint (LXX) - 2 Ki. 4:27; Ps. 19:6; 119:19; Prov. 27:12; Isa. 26:20; 40:27; Jer. 32:17; Zeph. 3:5 2Kings 4:27 When she came to the man of God to the hill, she caught hold of his feet. And Gehazi came near to push her away; but the man of God said, "Let her alone, for her soul is troubled within her; and the LORD has hidden (apokrupto) it from me and has not told me." Psalm 19:6 Its rising is from one end of the heavens, And its circuit to the other end of them; And there is nothing hidden from its heat. Psalm 119:19 I am a stranger in the earth; Do not hide Thy commandments from me. Proverbs 27:12 A prudent man sees evil and hides himself, The naive proceed and pay the penalty. Isaiah 26:20 Come, my people, enter into your rooms, And close your doors behind you; Hide for a little while, Until indignation runs its course. Isaiah 40:27 Why do you say, O Jacob, and assert, O Israel, "My way is hidden from the LORD, And the justice due me escapes the notice of my God "? As Barclay reminds us... Sometimes the history of Christianity can be presented in such a way that it sounds as if the gospel went out to the Gentiles only because the Jews would not receive it. Paul here reminds us that the salvation of the Gentiles is not an afterthought of God; the bringing of all men into his love was part of God’s eternal design. (Barclay, William: New Testament Words:. Westminster John Know Press, 1964)