Today’s Catechism sections discuss the command of Our Lord, “Do this in memory of me”, calling us to gather together to celebrate the Holy Mass. Supporting material comes from the “Didache”.

"Do this in memory of me"

1341 The command of Jesus to repeat his actions and words "until he comes" does not only ask us to remember Jesus and what he did. It is directed at the liturgical celebration, by the apostles and their successors, of the memorial of Christ, of his life, of his death, of his Resurrection, and of his intercession in the presence of the Father.165

1342 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.166

1343 It was above all on "the first day of the week," Sunday, the day of Jesus' resurrection, that the Christians met "to break bread."167 From that time on down to our own day the celebration of the Eucharist has been continued so that today we encounter it everywhere in the Church with the same fundamental structure. It remains the center of the Church's life.

1344 Thus from celebration to celebration, as they proclaim the Paschal mystery of Jesus "until he comes," the pilgrim People of God advances, "following the narrow way of the cross,"168 toward the heavenly banquet, when all the elect will be seated at the table of the kingdom.

The “Didache” (14) discusses the assembly of the faithful on the “Lord’s Day”.

Chapter 14. Christian Assembly on the Lord's Day

But every Lord's day gather yourselves together, and break bread, and give thanksgiving after having confessed your transgressions, that your sacrifice may be pure. But let no one that is at variance with his fellow come together with you, until they be reconciled, that your sacrifice may not be profaned. For this is that which was spoken by the Lord: In every place and time offer to me a pure sacrifice; for I am a great King, says the Lord, and my name is wonderful among the nations.

Footnotes

165 Cf. ⇒ 2 Cor 11:26.
166 ⇒ Acts 2:42, ⇒ 46.
167 ⇒ Acts 20:7.
168 AG 1; cf. ⇒ 1 Cor 11:26.