'Revelation 19:9
And the angel said to me, "Write this: Blessed are those who are invited to the marriage supper of the Lamb." And he said to me, "These are true words of God."
The Eucharist is the Pledge of the Glory to Come because it is the glory to come. The Eucharist is Jesus. What we shall receive in Heaven is full participation, not in something utterly different, but in the very same Jesus we receive in the Eucharist. To be sure, in one sense, everything will be different. Like the Risen Christ, the whole universe will be transfigured and we might not recognize the old girl at first. But when our eyes adjust to the light and we look again we will recognize that this place is Home, the place we've been looking for all our lives. And we will recognize that it has been among us, even on earth, because the same Jesus we know in the Eucharist is the Jesus who will welcome us to the Great and Ultimate Marriage Banquet at which He presides and offers Himself to us all.