Historical roots of Catholic Eucharistic theology

The historical roots of Catholic eucharistic theology begin with the same sources as do other Christian churches who express their faith in the "bread of life" found in the words of Jesus in Scripture. These include the Hebrew and Christian scriptures, the Church Fathers, and later Christian writers. While the word "Eucharist" (from the Greek) refers to Christ's prolongation of the Jewish Passover or "thanksgiving" meal, the gift of Communion, whereby, as Paul says, he fashions us into one body in him, came to signify God's greatest gift, for which Christians are most thankful.

The three synoptic Gospels and Paul's First Letter to the Corinthians contain versions of the Words of Institution: "Take, eat, this is my body.... Take, drink, this is my blood.... Do this in remembrance of me." All subsequent reference to the Communion bread and wine in the Eucharist is based on this injunction. A more detailed explanation of the Communion bread is New Testament passage John 6:47-67, key to understanding of the disciples of Jesus and the first Christians. There Jesus states:

Jesus then points to the need for correspondence between the bread as a sign (sacrament) and the life of those who would profit from it:

The New Testament tells of Jesus' celebration of the Jewish passover meal with his disciples before he died (though according to John's Gospel this meal would have been anticipated by Jesus – 19:14). At this meal the Jewish people recounted God's blessings toward them over each of the dishes. Jesus would turn one of the blessings over the bread and over the wine into symbols of the Father's love in his own life, death, and resurrection, and tell his disciples to do this in memory of him. As a thanksgiving meal, the Passover meal can be likened to the the todah or thanksgiving sacrifice (Lev 7:12-15). As a collective todah of Israel under the Mosaic covenant, it was the highest instance of todah sacrifice in the Hebrew Scripture. Likewise, the very term "Eucharist" (from the Greek eucharistia) reflects the centrality of thanksgiving. Christ's words of institution emphasize the essential todah elements of thanksgiving and remembrance, whose object in this case is his "body which is given for you" (Lk 22:19). As suggested by Jesus' use of Psalm 22 (Mk 15:34), a classic todah psalm, Christ's Passion, death, and resurrection exemplify the characteristic todah movement from lament to praise.

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