Praying the Liturgy of the Hours (the Breviary) Part II

​Praising God With the Church in Heaven
15. In the liturgy of the hours the Church exercises the priestly office of its Head and offers to God "without ceasing" [68] a sacrifice of praise, that is, a tribute of lips acknowledging his name. [69] This prayer is "the voice of a bride addressing her bridegroom; it is the very prayer that Christ himself, together with his Body, addresses to the Father." [70] "All who render this service are not only fulfilling a duty of the Church, but also are sharing in the greatest honor of Christ's Bride for by offering these praises to God they are standing before God's throne in the name of the Church, their Mother." [71]

16. When the Church offers praise to God in the liturgy of the hours, it unites itself with that hymn of praise sung throughout all ages in the halls of heaven; [72] it also receives a foretaste of the song of praise in heaven, described by John in the Book of Revelation, the song sung continually before the throne of God and of the Lamb. Our close union with the Church in heaven is given effective voice "when we all, from every tribe and tongue and people and nation redeemed by Christ's blood (see Rv 5:9) and gathered together into the one Church, glorify the triune God with one hymn of praise." [73]

The prophets came almost to a vision of this liturgy of heaven as the victory of a day without night, of a light without darkness: "The sun will no more be your light by day, and the brightness of the moon will not shine upon you, but the Lord will be your everlasting light" (Is 60:19; see Rv 21:23 and 25). "There will be a single day, known to the Lord, not day and night, and at evening there will be light" (Zech 14:7). Already "the end of the ages has come upon us (see I Cor 10:11) and the renewal of the world has been irrevocably established and in a true sense is being anticipated in this world." [74] By faith we too are taught the meaning of our temporal life, so that we look forward with all creation to the revealing of God's children. [75] In the liturgy of the hours we proclaim this faith, we express and nourish this hope, we share in some degree the joy of everlasting praise and of that day that knows no setting.

Petition and Intercession
17. But besides the praise of God, the Church in the liturgy of the hours expresses the prayers and desires of all the faithful; indeed, it prays to Christ, and through him to the Father, for the salvation of the whole world. [76] The Church's voice is not just its own; it is also Christ's voice, since its prayers are offered in Christ's name, that is, "through our Lord Jesus Christ," and so the Church continues to offer the prayer and petition that Christ poured out in the days of his earthly life [77] and that have therefore a unique effectiveness. The ecclesial community thus exercises a truly maternal function in bringing souls to Christ, not only by charity, good example, and works of penance but also by prayer. [78]

References 
(Vatican II documents:
SC= Sanctrosactum concilium;
PO=Presbyterum ordinis;
LG= Lumen gentium;
CD=Christus dominus)

56. See SC art. 83-84.
57. See SC art. 88.
58. See SC art. 94.
59. See PO no. 5.
60. CD no. 30.
61. SC art. 5.
62. See SC art. 83 and 98.
63. SC art. 7.
64. See SC art. 10.
65. SC art. 33.
66. See SC art. 24.
67. See SC art. 33.
68. 1 Thes 5:17.
69. See Heb 13:15.
70. SC art. 84.
71. SC art. 85.
72. See SC art. 83
73. LG no. 50; SC art. 8 and 104.
74. LG no. 48.
75. See Rom 8:19.
76. See SC art. 83.
77. See Heb 5:7.
​78. See PO no. 5