Although the development of the Eucharistic rites extended over several centuries, it is safe to say that for the first millennium of Christianity the teaching of St. Augustine in the fifth century on Real Presence summed up Church belief: “Once the bread that you see on the altar is sanctified by the Word of God, it is the body of Christ. And once the chalice is sanctified by the word of God, what the chalice contains is the blood of Christ.” [Sermons 227] It is easy to overlook, though, how the guarantee for this miracle is “the Word of God,” i.e., Scripture, specifically John 6, the famous Breads Narrative. Strange as it may seem today, Martin Luther held precisely the same belief. In 1000 A.D., had he been alive, Luther would have taught in full harmony with the Church. [I am painting here with a broad brush; a richer history of Eucharistic theological development is found, for example, in Doors to the Sacred [2014, pp. 239-315]
Late in the Dark Ages a monk theologian named Radbertus put forward the first metaphysical definition of the process of Eucharistic consecration, what we know today as “transubstantiation.” The term describes how the presence of Christ enters the bread and wine, namely, by displacing them. The appearance of bread and wine remains; in the early medieval philosophy of the day, the appearance, taste, and texture of communion remains. As my first communion class was taught in 1956, “the substance of the bread becomes Christ; the accidents-odor, taste, shape, weight-remain the same.” Ask an old Catholic about “substance and accidents.”
By the year 1000 A.D. a theologian, Berengar of Tours, put forward a novel formulation of the Eucharistic food. Berengar was a consummate realist; if communion looked like bread and wine to the human senses, then bread and wine it must be. When one received communion, he argued, one was receiving actual bread and wine. Receiving was not an empty act for Berengar; in his line of thinking, a faithful believer received Christ spiritually. There was a true change in the bread and wine during the consecration, but the change was spiritual while the substance of bread and wine remained to be eaten.
Berengar posed the first major threat to the Catholic doctrine of Real Presence, and as could be expected, the great minds of Catholic universities addressed the changes in the bread and wine with increasing precision. St. Thomas Aquinas [1225-1274 A.D.] spoke for many when he stated that the Mass itself was not a sacrament, but rather a sacred action that produced a sacrament, i.e., the consecrated species.] Using the terminology of Aristotle, Thomas provided the language for the change in the bread and wine. He used the substance-accidents formulary: that while the sacred food may appear to be bread and wine, its essence was the full presence of Jesus Christ, second person of the Trinity. The transubstantiation formulary was promulgated for the whole Church at the Council of Trent [1545-1563] To believe that these simple elements of food hid the eternal presence of God became not only a bedrock doctrine of belief, but an inspiration for a Eucharistic piety that continues to this day, such as Eucharistic adoration, benediction, etc. A product of this era is the Eucharistic hymn Adoro te, devote, written by St. Thomas himself. Note the emphasis upon faith in what cannot be seen, and trust in the Word of God that Christ is indeed present:
I devoutly adore you, O hidden Deity,
Truly hidden beneath these appearances.
My whole heart submits to you,
And in contemplating you, It surrenders itself completely.
Sight, touch, taste are all deceived in their judgment of you,
But hearing suffices firmly to believe.
I believe all that the Son of God has spoken;
There is nothing truer than this word of truth.
On the cross only the divinity was hidden,
But here the humanity is also hidden.
Yet believing and confessing both,
I ask for what the repentant thief asked.
I do not see the wounds as Thomas did,
But I confess that you are my God.
Make me believe more and more in you,
Hope in you, and love you.
O memorial of our Lord's death!
Living bread that gives life to man,
Grant my soul to live on you,
And always to savor your sweetness.
Martin Luther would not appear on the scene until the early 1500’s, and as we saw in earlier posts, he believed that many of the beliefs and practices of the Church were wrong, primarily in their distance from Sacred Scripture, which he believed to be the final arbiter of God’s revelation. Regarding the Eucharist and Christ’s Real Presence, Luther brought into the discussion his distaste for the philosophical system of St. Thomas Aquinas and the linguistics of describing reality, a system known as “scholasticism.” Luther was troubled that scholasticism, as defined in his day, “boxed” Christian faith into certainties that could not be clearly substantiated by Scripture. The Indulgence controversy, which thrust him into the public eye, is just one example.
As a Catholic academic and Augustinian monk, Luther shared belief in Real Presence, though not in the accepted formula of a St. Thomas Aquinas. In the process of transubstantiation as defined by scholastics, the substance or reality of bread and wine was obliterated [my word] and replaced by the reality of Christ himself. Luther—a scripture scholar—returned to the bible, specifically John 6, and derived his understanding that the correct doctrinal understanding of communion is the eating and drinking of Christ as bread and wine. To say, as the scholastics did, that the consecrated bread and wine no longer existed, was to contradict Jesus’ very words, “I am the living bread…he who feeds on me will live forever….”
Luther maintained that the essence of bread and wine was not removed in transubstantiation and argued that the communion meal was both bread and wine and the actual divine Lord. Here he makes an intriguing analogy, based upon one of Christianity’s most basic doctrines, the Incarnation, in which the eternal Lord became human, born a man. Put simply, the Church has taught definitively since the Councils of Ephesus [432 A.D.] and Chalcedon [451 A.D.] that the divinity of Christ never diminished the humanity of Christ, despite several attempts of heretical communities to assert otherwise. If the humanity of Christ is not diminished by his divine identity, why would the bread and wine need to be evacuated at the time of consecration?
Following this path of reasoning, Luther saw no reason to claim that the bread and wine at Mass lost its identity at the words of the consecration. Rather, he saw the Mass as a celebration of God’s love expressed in a reenactment of the Incarnation. The scholastic argument that the bread and wine ceased to exist at the time of the consecration seemed to Luther to run contradictory to God’s immersion in the world. Later Protestant thinkers applied the term consubstantiation to Luther’s thinking, after his death, the coexistence of bread/wine with the divine presence in the communion sacrament.
Luther’s theorizing on the sacraments in general was considered heretical by the Church, and the Council of Trent [1545-1563] reinforced the scholastic formulations of Catholic truths. St. Thomas Aquinas would eventually be declared the official theologian of the Church. Para. 1376 of the Catechism  employs the scholastic terminology to describe Real Presence in the context of the Mass, specifically consecration. By the time of the Council of Trent , Protestant reformers were running far ahead of the aging Luther in their theology and practices of reform. Huldrych Zwingli, for example, stripped the Mass of much of its traditional meaning, speaking of the Catholic worship rite as a symbolic action only; this concept deeply upset Luther who believed strongly in Real Presence despite his objections to its doctrinal linguistics.
Luther died in 1546, just as the Church’s reform Council of Trent was working toward an opening quorum. Trent wished to clearly define Church doctrine in its traditional language in an age where Protestantism was splitting off in multiple directions, and it was not likely to have much patience with the speculations of Luther, Zwingli, or John Calvin, to name a few reform thinkers of the sixteenth century. Vatican II [1962-1965], by contrast, was called to address the postwar world and, among other things, to heal divisions between the churches [i.e., ecumenism]. Regarding Real Presence, the Church continues to use the scholastic/Thomistic formulation, but Vatican II called for greater respect of separated churches whose understanding of Eucharist differs from the Roman Catholic belief. Although interfaith communion is generally not permitted in Canon Law [though there are a few exceptions], Catholics are called upon to believe that Protestant communities which celebrate communion rites in good faith, are not devoid of a true spiritual communion with Jesus and should be respected for that fact.