The Book of Common Prayer says of The Holy Communion that it is, “commonly called the Mass.”
The word “Mass” is probably derived from the Latin dismissal pronounced in the old service by the priest at the end, “Ite, missa est.” The word is related to “mission.” Having received the Sacrament, the congregation are being sent out as missionaries.
Holy Communion describes part of the meaning of this service as a communal meal by which we express our spiritual meeting with Jesus and our fellowship with one another. But it is more even than that…
Another word for this service is “Eucharist” which means thanksgiving. Here we give thanks for Christ’s sacrifice on the Cross for our salvation.
Or “The Lord’s Supper” gives the origin of this ritual as The Last Supper which Jesus ate with his disciples before his Crucifixion. Jesus said, “Do this in remembrance of me.” But this is much more than a memorial, for Jesus has promised to be really present whenever we follow his commandment.
When we receive the Sacrament we are meeting the Lord as truly as the disciples met him at that Last Supper in Jerusalem.
Roman Catholics and some other Christians use “Transubstantiation” as a technical word to describe what happens at the Mass. This does not mean that the bread and wine become the physical Body and Blood of the Lord. Transubstantiation derives from an ancient way of thinking in which “substance” did not mean matter or stuff, but the true character and reality of a thing. So, because of Our Lord’s promise that he will be truly with us when the priest blesses the bread and the wine, we can safely take it on trust that the real Person Jesus is with us.
So a most helpful phrase is his Real Presence.
How Jesus is present in the Mass is a mystery. The fact that he is present is a reality. And that is how, believing this Holy Mystery, Queen Elizabeth I, arriving at the Tower of London, declared her faith:
Christ was the word that spake it.
He took the bread and break it;
And what his words did make it
That I believe and take it.
We believe that Jesus is really with us in the Mass precisely because he promised he would be.