Today one of the strongest impulses towards the renewal of the theological concept of the church comes from theology of mission.
To grasp the missionary church theologically in a world-wide context means understanding it in the context of the missio dei. Mission comprehends the whole of the church, not only parts of it, let alone the members it has sent out. To proclaim the gospel of the dawning kingdom is the first and most important element in the mission of Jesus, the mission of the Spirit, and the mission of the church; but it is not only one.
Mission embraces all activities that serve to liberate man from his slavery in the presence of the coming God, slavery which extends from economic necessity to God forsakenness. Evangelization is mission, but mission is not mere evangelization. In the missionary church the widow who does charitable works belongs to the same mission as the bishop who leads the church or the preacher of the gospel.
The real point is not to spread the church but to spread the kingdom. The goal is not the glorification of the church but the glorification of the Father through the Son in the Holy Spirit.
Jurgen Moltmann, The Church in the Power of the Spirit (Harper & Row, Publishers, 1975), 10