2 For the liturgy, "through which the work of our redemption is accomplished," most of all in the divine sacrifice of the Eucharist, is the outstanding means whereby the faithful may express in their lives, and manifest to others, the mystery of Christ and the real nature of the true Church. It is of the essence of the Church that she be both human and divine, visible and yet invisibly equipped, eager to act and yet intent on contemplation, present in this world and yet not at home in it; and she is all these things in such wise that in her the human is directed and subordinated to the divine, the visible likewise to the invisible, action to contemplation, and this present world to that city yet to come, which we seek . While the liturgy daily builds up those who are within into a holy temple of the Lord, into a dwelling place for God in the Spirit , to the mature measure of the fullness of Christ , at the same time it marvelously strengthens their power to preach Christ, and thus shows forth the Church to those who are outside as a sign lifted up among the nations under which the scattered children of God may be gathered together , until there is one sheepfold and one shepherd .
Source: Sacrosanctum Concilium (Vatican.va)