[Reviewing 20th-century research into the origins of the Eucharist, the author observes that many of the Church’s theologians have yet to appropriate the significance of what is commonly accepted as historical fact by exegetes and liturgical theologians, namely, that there is no clear line of development from the Last Supper of Jesus to the theologically rich Eucharistic Prayers of the patristic golden age. The implications of this for methodology, for systematic theology and ecclesiology, for liturgical and ecumenical theology, and for pastoral theology and homiletics are then briefly discussed.]