The Mass is well framed in the last chapter of Luke:
"their hearts were burning in their breasts as He explained Scripture to them"....and they asked Him to "remain with them" and He answered their request and ... "they recognized Him in the breaking of the bread."
The two parts of the Mass are the reading and explanation of the Scriptures (the Old Testament and/or the Epistles, the Psalms, and the Gospel), followed by words of Consecration and the Breaking of the Bread.
We recognize Him in the "breaking of the Bread" and the reception of his Body, Blood , Soul and Divinty in the Eucharist. In this way, by Word and Sacrament, He fulfills our desire for Him to "remain with us."
And up to this day, He does so, at all hours around all the world.