-- Jn 15:18-21
Though already present in his Church, Christ's reign is nevertheless yet to be fulfilled "with power and great glory" by the King's return to earth. This reign is still under attack by the evil powers, even though they have been defeated definitively by Christ's Passover. Until everything is subject to him, "until there be realized new heavens and a new earth in which justice dwells, the pilgrim Church, in her sacraments and institutions, which belong to this present age, carries the mark of this world which will pass, and she herself takes her place among the creatures which groan and travail yet and await the revelation of the sons of God." That is why Christians pray, above all in the Eucharist, to hasten Christ's return by saying to him: Marana tha! "Our Lord, come!"
-- CCC 671