Catechism of the Catholic Church

Why does the Church celebrate the liturgy so often?
The people of Israel interrupted their work “seven times a day” (Ps 119:164) in order to praise God. Jesus participated in the liturgy and prayer of his people; he taught his disciples to pray and gathered them in the Upper Room so as to celebrate with them the liturgy of all liturgies: the gift of himself in the Last Supper. The Church, which calls us to the liturgy, obeys his command, “Do this in remembrance of me.”

Just as a man breathes air in order to stay alive, so too the Church lives and breathes by celebrating the liturgy. God himself is the one who breathes new life into her day by day and enriches her with gifts through his Word and his sacraments. We can use another image, too: every liturgy is like a rendezvous of love that God writes on our calendar. Anyone who has already experienced God’s love is glad to go to church. Someone who from time to time feels nothing and goes nevertheless shows God his faithfulness.