Because of the tabernacles in our churches, we Catholics could easily miss some of what Luke is trying to tell us in today's gospel pericope.
Reserving the Blessed Sacrament is a rather late development in the church's history. As a seminarian in Rome in the mid-60s, I'd sometimes participate in a game of "find the original tabernacle" in some of the eternal city's oldest churches. Most of the time there was no tabernacle to find. At most there'd be a small metal door covering a hollowed out area in a wall or pillar in which pieces of the Eucharistic bread earmarked for the sick or imprisoned were kept. Never were these in a central place, or constructed in such a way that the faithful could gather for "Eucharistic devotion" in front of them.
Well-known theologian Karl Rahner was convinced that the earliest Christians believed the risen Jesus was only present in the Eucharistic bread and wine as long as the Eucharistic community was present. When the Lord's Supper was finished, they seemed to think he was no longer present in any "leftovers," except in those earmarked pieces I mentioned above. They knew nothing about a "generic presence" of Jesus which could be kept secure and unchanging in a special revered receptacle. Thus they saw no reason to have tabernacles.
Even during my Christmas homilies, I always remind the community that Christmas can never be compared to Easter. If the Galilean carpenter we imitate hadn't risen from the dead, we never would have started celebrating his birth. That's why Luke's Peter puts the resurrection at the center of his Acts Pentecost speech. "God raised this Jesus;" Peter proclaims, "of this we are all witnesses."
The author of I Peter agrees. This anonymous writer quickly cuts to the heart of Christian belief. "He (Jesus) was known from the foundation of the world but revealed in the final time for you, who through him believe in God who raised him from the dead and gave him glory, so that your faith and hope are in God."
If Jesus' resurrection is the most important part of our faith, where and how is he the most alive and among us? Luke's Emmaus narrative provides us with a black and white answer.
Notice how Jesus starts his encounter with his "wrong-way" disciples. "Beginning with Moses and all the prophets, he interpreted to them what referred to him in all the Scriptures." Commentators frequently refer to his use of Scripture as the "Liturgy of the Word." It's eventually followed by the disciples urging him to stay with them, even sharing a meal: the "Liturgy of the Bread." "It happened that, while he was with them at table, he took bread, said the blessing, broke it, and gave it to them. With that their eyes were opened and they recognized him ..." The risen Jesus surfaces in the action we most anticipate finding him: the Eucharist.
Of course, following early Christian belief, he immediately "vanished from their sight." The understanding is that he'll again be recognizable the next time they gather for the Lord's Supper. It's important that Luke has the two tell their fellow disciples that he was made known to them not in the bread, but in the breaking of the bread; in the whole action of sharing a Eucharistic meal.
For good reason our diocesan cathedral, remodeled immediately after Vatican II, located its tabernacle in a special Blessed Sacrament Chapel, distinct from the area in which the community normally gathers on weekends to break bread. Though we certainly believe in Jesus' presence in the reserved Eucharistic bread, back then, fresh from the council's liturgical insights and dependence on Scripture, we didn't want that reserved presence to be a distraction to our surfacing the risen Jesus in our midst during the actual celebration of the Eucharist. We were encouraged to experience him/her in a way different from his tabernacle presence.