In this extract from Desiring the Kingdom, James K. A. Smith draws attention to how the Eucharist is forward looking.
'there's a certain sense in which the celebration of the Lord's Supper should be experienced as a kind of sanctified letdown. For every week that we celebrate the Eucharist is another week that the kingdom and its feast have not yet fully arrived. And every week the words of institution remind us of this fact, for we do it "until he comes." By this I don't mean to denigrate the peace, joy, and nourishment that is found in the Supper; rather, the point is to emphasise that the Eucharist is an eschatological supper. It's sort of a meal "to go", or at least a meal on the way. It's a table in the wilderness (Ps 78.19) and in the presence of our enemies (Ps 23.5), and so there's a certain sense in which we eat it "on the run" - not because of the frenetic pace of consumption and distraction that so often finds us in the drive-thru and eating fast food in the car, but rather because the Lord's Supper is an anticipatory meal that we eat while we sojourn in the earthly city, looking forward to the marriage supper of the Lamb (Rev 19.9). So the Lord's Supper is a foretaste of the feast in the kingdom, which means its meaning has to be situated within an eschatological horizon. It is a meal that constitutes us as an eschatological people: while it recalls and recapitulates Christ's death, burial, and resurrection, the Supper looks ahead to the feast in the kingdom. As such, "the Eucharist should be understood as a sign of the renewed creation. The Eucharist is our model of the eschatological order, a microcosm of the way things really ought to be" (Leithart). Thus it is a normative meal: by showing us a foretaste of how things ought to be, the practice of the Lord's Supper carries norms in it, and these norms constitute both a basis of critique for the present order, as well as hints as to how the church should order itself as a polis that is itself a foretaste of the coming community.
James K. A. Smith, Desiring the Kingdom: Worship, Worldview, and Cultural Formation (Baker, 2009), p.200.