For I received from the Lord what I also handed on to you, that the Lord Jesus on the night when he was betrayed took a loaf of bread, and when he had given thanks, he broke it and said, ‘This is my body that is for[a] you. Do this in remembrance of me.’ In the same way he took the cup also, after supper, saying, ‘This cup is the new covenant in my blood. Do this, as often as you drink it, in remembrance of me.’ For as often as you eat this bread and drink the cup, you proclaim the Lord’s death until he comes.
(Church in Wales Lectionary, New Revised Standard Version) 68-75 AD
This little passage from 1 Corinthians, Chapter 11, is of great importance. It's the earliest account that we have of the Last Supper, that would become our Eucharist. We might be forgiven for thinking that the earliest story of this last meal that Jesus held with his disciples came from one of the Gospels, but they were written after Paul's letter to Corinth. He writes around 53 AD and the first Gospel that of St Mark, doesn't appear until between 68 and 75 AD.
Paul berates the Corinthians for treating the Lord's Supper as an ordinary meal. They bring their own food but don't share it with the poorer members of the congregation. Paul tells them to eat their ordinary meals at home. This is a symbolic meal that should change them spiritually. He reminds them that at the Last Supper, Jesus:
and the disciples:
Paul reminds them that the bread and wine are outward signs of Christ's body and blood - his body broken and his blood shed - and they do this to remember Christ's action in dying for them, and to bring them ever closer to Him as they commit their lives afresh to Him once more.
Lord Jesus Christ,
may we fully appreciate
what we do at the Eucharist:
that we consume bread and wine
to remember Your body was broken,
and Your blood was shed for us.
May we never take this action for granted,
and may these physical actions
make spiritual changes to our lives.
Amen.
If you want a simple explanation of The Eucharist (which means 'Thanksgiving'), you might look up this site produced by the BBC: