Redemptoris Mater §41

⁴¹ Through her mediation, subordinate to that of the Redeemer, Mary contributes in a special way to the union of the pilgrim Church on earth with the eschatological and heavenly reality of the Communion of Saints, since she has already been "assumed into heaven." The truth of the Assumption, defined by Pius XII, is reaffirmed by the Second Vatican Council, which thus expresses the Church's faith: "Preserved free from all guilt of original sin, the Immaculate Virgin was taken up body and soul into heavenly glory upon the completion of her earthly sojourn. She was exalted by the Lord as Queen of the Universe, in order that she might be the more thoroughly conformed to her Son, the Lord of lords (cf. Rev. 19:16) and the conqueror of sin and death." In this teaching Pius XII was in continuity with Tradition, which has found many different expressions in the history of the Church, both in the East and in the West. By the mystery of the Assumption into heaven there were definitively accomplished in Mary all the effects of the one mediation of Christ the Redeemer of the world and Risen Lord: "In Christ shall all be made alive. But each in his own order: Christ the first fruits, then at his coming those who belong to Christ" (1 Cor. 15:22-23). In the mystery of the Assumption is expressed the faith of the Church, according to which Mary is "united by a close and indissoluble bond" to Christ, for, if as Virgin and Mother she was singularly united with him in his first coming, so through her continued collaboration with him she will also be united with him in expectation of the second; "redeemed in an especially sublime manner by reason of the merits of her Son," she also has that specifically maternal role of mediatrix of mercy at his final coming, when all those who belong to Christ "shall be made alive," when "the last enemy to be destroyed is death" (1 Cor. 15:26)." Connected with this exaltation of the noble "Daughter of Sion" through her Assumption into heaven is the mystery of her eternal glory. For the Mother of Christ is glorified as "Queen of the Universe." She who at the Annunciation called herself the "handmaid of the Lord" remained throughout her earthly life faithful to what this name expresses. In this she confirmed that she was a true "disciple" of Christ, who strongly emphasized that his mission was one of service: the Son of Man came not to be served but to serve, and to give his life as a ransom for many" (Mt. 20:28). In this way Mary became the first of those who, "serving Christ also in others, with humility and patience lead their brothers and sisters to that King whom to serve is to reign," and she fully obtained that "state of royal freedom" proper to Christ's disciples: to serve means to reign! "Christ obeyed even at the cost of death, and was therefore raised up by the Father (cf. Phil. 2:8-9). Thus he entered into the glory of his kingdom. To him all things are made subject until he subjects himself and all created things to the Father, that God may be all in all (cf. 1 Cor. 15:27-28)." Mary, the handmaid of the Lord, has a share in this Kingdom of the Son. The glory of serving does not cease to be her royal exaltation: assumed into heaven, she does not cease her saving service, which expresses her maternal mediation "until the eternal fulfillment of all the elect." Thus, she who here on earth "loyally preserved in her union with her Son unto the Cross," continues to remain united with him, while now "all things are subjected to him, until he subjects to the Father himself and all things." Thus in her Assumption into heaven, Mary is as it were clothed by the whole reality of the Communion of Saints, and her very union with the Son in glory is wholly oriented towards the definitive fullness of the Kingdom, when "God will be all in all." In this phase too Mary's maternal mediation does not cease to be subordinate to him who is the one Mediator, until the final realization of "the fullness of time," that is to say until "all things are united in Christ" (cf. Eph. 1:10).