CCC 1342
Christian Mystery›SECTION TWO THE SEVEN SACRAMENTS OF THE CHURCH›CHAPTER ONE THE SACRAMENTS OF CHRISTIAN INITIATION›III. The Eucharist in the Economy of Salvation
From the beginning the Church has been faithful to the Lord's command. of the Church of Jerusalem it is written: They devoted themselves to the apostles' teaching and fellowship, to the breaking of bread and the prayers.... Day by day, attending the temple together and breaking bread in their homes, they partook of food with glad and generous hearts.