III. When is the Liturgy Celebrated?

From The Catechism of the Catholic Church

1167
Sunday is the pre-eminent day for the liturgical assembly, when the faithful
gather “to listen to the word of God and take part in the Eucharist, thus
calling to mind the Passion, Resurrection, and glory of the Lord Jesus, and
giving thanks to God who ‘has begotten them again, by the resurrection of Jesus
Christ from the dead’ unto a living hope”:⁴⁰

PART TWO: THE CELEBRATION OF THE CHRISTIAN MYSTERY

SECTION ONE THE SACRAMENTAL ECONOMY
- CHAPTER TWO THE SACRAMENTAL CELEBRATION OF THE PASCHAL MYSTERY
  - Article 1 CELEBRATING THE CHURCH’S LITURGY
    - III. When is the Liturgy Celebrated?

From The Catechism of the Catholic Church – rosary.team