Lord's Supper in Reformed theology

In Reformed theology, the Lord's Supper or Eucharist is a sacrament that spiritually nourishes Christians and strengthens their union with Christ. The outward or physical action of the sacrament is eating bread and drinking wine. Reformed confessions, which are official statements of the beliefs of Reformed churches, teach that Christ's body and blood are really present in the sacrament and that believers receive, in the words of the Belgic Confession, "the proper and natural body and the proper blood of Christ." The primary difference between the Reformed doctrine and that of Catholic and Lutheran Christians is that for the Reformed, this presence is believed to be communicated in a spiritual manner by faith rather than by oral consumption. The Reformed doctrine of real presence is called "pneumatic presence" (from pneuma, a Greek word for "spirit"; alternatively called "spiritual real presence" or "mystical real presence").

Early Reformed theologians such as John Calvin and Huldrych Zwingli rejected the Roman Catholic belief in transubstantiation, that the substances of bread and wine of the Eucharist change into Christ's body and blood. They taught that Christ's person, including his body and blood, are presented to Christians who partake of it in faith. They also disagree with Martin Luther who taught that Christ's body is received orally in the sacramental "elements" of bread and wine. Later Reformed orthodox theologians continued to teach views similar to that of Calvin and Zwingli. In the modern period, Karl Barth espoused a symbolic view that the sacrament only communicates God's promises rather than functioning to actually confer these promises. Other Reformed theologians continue to teach the traditional Protestant view.