One of the most common metaphors used in the New Testament to describe the relation of the church to the gospel is that of stewardship. The church, and especially those called to any kind of leadership in the church, are servants entrusted with that which is not their property but is the property of their Lord. That which is entrusted is something of infinite worth as compared with the low estate of the servants in whose hands it is placed. They are but mud pots; but that which is entrusted to them is the supreme treasure (II Cor. 4:7). The treasure is nothing less than “the mysteries of God” (I Cor. 4:1), “the mystery of the gospel” (Eph. 6:19), “the mystery which was kept secret for long ages but is now disclosed and… made known to all nations… to bring about the obedience of faith” (Rom. 16:25-26). It is “the mystery of his will… to unite all things in him” (Eph. 1:9-10). It is the open secret of God’s purpose, through Christ, to bring all things to their true end in the glory of the triune God. It is open in that it is announced in the gospel that is preached to all the nations; it is a secret in that it is manifest only to the eyes of faith. It is entrusted to those whom God has given the gift of faith by which the weakness and foolishness of the cross is known as the power and wisdom of God. It is entrusted to them not for themselves but for all the nations. It is Christ in them, the hope of glory.
Lesslie Newbigin. The Open Secret: An Introduction to the Theology of Mission (Kindle Locations 2551-2560). Kindle Edition.