III. When is the Liturgy Celebrated?

From The Catechism of the Catholic Church

1169
Therefore Easter is not simply one feast among others, but the “Feast of
feasts,” the “Solemnity of solemnities,” just as the Eucharist
is the “Sacrament of sacraments” (the Great Sacrament). St.
Athanasius calls Easter “the Great Sunday”⁴³ and the Eastern
Churches call Holy Week “the Great Week.” the mystery of the
Resurrection, in which Christ crushed death, permeates with its powerful energy
our old time, until all is subjected to him.

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