This volume serves as the foundational liturgical resource for the Roman Catholic Church, addressing the necessity of structured daily prayer during the Advent, Christmastide, and early Ordinary Time seasons. The text is compiled by the Church to provide a standardized framework for clergy and laity to participate in the Liturgy of the Hours. It organizes daily devotions into specific temporal segments, ensuring that the rhythm of the liturgical calendar is maintained through consistent, communal, or individual recitation of prayers and scripture.

This work is regarded as the definitive, authoritative text for the Roman Catholic Liturgy of the Hours, functioning as a primary tool for religious observance. Its structure is designed for high-density, daily use by practitioners seeking to align their personal devotion with the official liturgical calendar of the Church.