The paragraph that follows is one of the best summaries of the importance and purpose of the Liturgy of the Hours:
349. In the celebration of the office for the dead members of the Christian community gather to offer praise and thanks to God especially for the gifts of redemption and resurrection, to intercede for the dead, and to find strength in Christ’s victory over death. When the community celebrates the hours, Christ the Mediator and High Priest is truly present through his Spirit in the gathered assembly, in the proclamation of God’s word, and in the prayer and song of the Church (GILH 13). The community’s celebration of the hours acknowledges that spiritual bond that links the Church on earth with the Church in heaven, for it is in union with the whole Church that this prayer is offered on behalf of the deceased.