III. When is the Liturgy Celebrated?

From The Catechism of the Catholic Church

The Lord’s day, the day of
Resurrection, the day of Christians, is our day. It is called the Lord’s day
because on it the Lord rose victorious to the Father. If pagans call it the
“day of the sun,” we willingly agree, for today the light of the
world is raised, today is revealed the sun of justice with healing in his
rays.³⁹

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