“This text in the valuable . . . series, Milestones in Catholic Theology, makes available once again an essay written by a leading force for liturgical renewal in the first half of the twentieth century. Casel, a monk of Maria Laach, writes eloquently of the need to see the act of worship as the central act in the Christian religion, as attention to sacred mystery is at the core of religion itself. A major influence on the Second Vatican Council’s Decree on the Liturgy, Casel writes sublimely of the depths of the mystery of Christ in his passion and resurrection and the presence of this mystery in the act of worship, but he does so here in spiritual writing that is quite accessible. The text is provided with a helpful little historical introduction by Cavanaugh.”