Liturgy of the Hours
The Liturgy of the Hours, or the Opus Dei, the Work of God, as Saint Benedict put it, is the Church's just response of praise and thanksgiving to God our Father for the Salvation which He accomplished in Christ Jesus, our Lord.
Also known as the Divine Office, this prayer of the Church is a liturgy, that is, it is Christ's action to which we are mystically joined by the grace of the Sacrament of Baptism. Composed of Psalms, canticles, antiphons and prayers, the Liturgy of the Hours finds its historical roots in the ancient and venerable prayer of the synagogue. It was here that Jesus, our Lord, spoke these same Scriptures and prayers as He offered praise, petition and worship to His heavenly Father.
The Church, the Mystical Body of Christ, continues Christ's perfect and eternal praise of the Father through the liturgical prayer of the Church. Liturgical prayer, the sacramental life of the Church, procures God's glory directly. All other forms of prayer procure the Divine glory indirectly, that is, in so far as the action is good and one's intention is proper.
"Christ has bequeathed to His spouse, the Church, all the riches of His merits, His graces, His teaching, and the power to continue on earth the work of the glorification of the Most Holy Trinity" (Bl. Columba Marmion: Christ the Ideal of the Monk).
The Church's prayer to the Father is Christ: His incarnation, passion, death, resurrection, ascension into heaven, and the pentecost of the Spirit. This is the Paschal Mystery we encounter in the Holy Eucharist. Having encountered so great a love poured out for us, the Church bursts forth in praise and thanksgiving. Saint Augustine wrote: "They are two in one flesh, why should they not be two in one voice?" In the Church we prolong and complete the adoration of the Father begun in Christ and continued by His grace. "I will sing of thy steadfast love, O Lord, forever; with my mouth I shall proclaim thy faithfulness to all generations" (Ps 89).
Saint John Chrysostom put it best: "Every time the Christian people apply themselves to the recitation of the Psalms they become like a lyre ready to vibrate under the hand of the Holy Spirit, who touches the most profound chords of our hearts and draws from them the praise which God deserves."