Why is the Eucharist not merely a symbol?

Before answering, a misunderstanding must be defused. The debate does not pit “symbol” on one side against “reality” on the other, as if Catholics denied all symbolic value to bread and wine. Bread signifies nourishment, wine signifies joy and blood; the Eucharist is indeed a sign. The real question lies elsewhere.

What the “only a symbol” thesis holds

The opposing position — historically that of the Swiss reformer Ulrich Zwingli (1484-1531) — can be summed up as follows: at the Supper, the bread remains bread. It does not become the body of Christ; it recalls it. The “Lord's Supper” is a memorial, a commemorative meal in which the community remembers the death of Jesus and proclaims its faith. The “is” of “this is my body” must be read as “this signifies my body,” exactly as when Jesus says “I am the door” (Jn 10:9) without being a wooden door. The key verse invoked is John 6:63: “It is the spirit that gives life; the flesh is capable of nothing.”^[4]

What the Catholic faith confesses

The Church does not merely say that Christ is present “more intensely” in a symbol. She affirms a change of reality. The Catechism takes up word for word the Council of Trent:

“In the most blessed sacrament of the Eucharist ‘the body and blood, together with the soul and divinity, of our Lord Jesus Christ and, therefore, the whole Christ is truly, really, and substantially contained.’” — Catechism of the Catholic Church, § 1374, citing the Council of Trent^[5]

Three adverbs carry all the weight: truly (it is not an image), really (it is not a mere subjective thought of the believer), substantially (it is not only the energy or virtue of Christ, but his very substance). After the consecration, the Church says, what lies on the altar is no longer bread: it is Christ, under the appearances of bread^[6].

Where the disagreement really lies

The disagreement is therefore not symbol versus non-symbol, but “symbol only” versus “a symbol that contains and gives what it signifies.” That is the very definition of the Catholic sacrament: a sign that “effects what it signifies”^[7]. The question of this article amounts exactly to asking: when Jesus took the bread, did he institute a reminder — or did he give himself?

Four great answers have been given in Christian history. Distinguishing them clarifies the whole debate.

Only memorialism denies substantial presence: for Zwingli, the Supper is a memorial that nourishes faith — remembrance of Christ's death and spiritual reception by faith (Exposition of the Christian Faith, 1531) — without the body of Christ being substantially present therein. It is not, in his eyes, a rite empty of all spiritual effect; it is substantial presence that he rejects. The three other positions, despite their profound differences, all refuse to say “it is only a symbol” — including Luther, who broke with Zwingli precisely on this point (see below, the Marburg Colloquy). In other words, the purely symbolist reading is late in date and long remained marginal in Christian history.

Two words in the table call for a gloss. In Calvin, the “virtue” (virtus) of Christ denotes his efficacy, his operative power communicated to the believer by the Holy Spirit — not a mere moral influence. And what the table calls sacramental union, the term of the Lutheran confessions, is often called “consubstantiation” in textbooks: a word Lutherans generally reject, since it suggests a philosophical system foreign to Luther.

The most decisive text is not first the narrative of the Supper: it is the long discourse spoken by Jesus at Capernaum, about a year before his Passion, reported in chapter 6 of John's Gospel. There Jesus faces the objection “it is only an image” head-on — and refuses to yield to it.

“My flesh is true food”

After multiplying the loaves, Jesus presents himself as the “bread of life.” The discourse could remain metaphorical — until the moment when Jesus deliberately hardens his language:

“I am the living bread which came down from heaven; if any one eats of this bread, he will live for ever; and the bread which I shall give for the life of the world is my flesh. […] For my flesh is food indeed, and my blood is drink indeed. He who eats my flesh and drinks my blood abides in me, and I in him.” — Gospel according to Saint John 6:51, 55-56^[8]

One detail of the Greek text carries weight. From verse 54 onward, John stops using the ordinary verb for “eating” (phagein) and switches to the verb trōgein — “to chew,” “to crunch,” a concrete, fleshly word. This deliberate hardening of vocabulary sits ill with the idea that Jesus simply meant “believe in me”^[9]. It does not settle the debate by itself: trōgein also has the general sense of “to eat,” and the Greek lexicon records at least one figurative use. The choice of verb thus supports the realistic reading without by itself demonstrating the impossibility of any figure.

“This is a hard saying”: Jesus lets the disciples walk away

The strongest indication in favor of the realistic sense, in the eyes of the Catholic tradition, is the reaction of the audience — and Jesus' reaction to their scandal. The disciples understand that he speaks of really eating his flesh, and it revolts them.

“Many of his disciples, when they heard it, said, ‘This is a hard saying; who can listen to it?’ […] After this many of his disciples drew back and no longer went about with him.” — Gospel according to Saint John 6:60, 66^[10]

Here is the point that causes difficulty for the symbolist reading: Jesus lets them go. Often in the Gospels, when a hearer understands Jesus too literally — Nicodemus thinking one must “enter a second time into his mother's womb” (Jn 3:4), the Samaritan woman thinking of ordinary water (Jn 4:15) — Jesus raises the remark toward its true meaning. Here, on the contrary, as many disciples walk away scandalized by the realism of his words, he does not say: “Wait, you misunderstood; I was speaking figuratively.” He turns to the Twelve and asks whether they too will leave (Jn 6:67). That a master should watch many of his disciples drift away over a mere misunderstanding of vocabulary without dispelling it — the Catholic tradition reads in this the sign that the realistic meaning is indeed the one he intended^[11].

“The flesh is capable of nothing”: the objection turned back

There remains the verse the symbolists always cite: “It is the spirit that gives life; the flesh is capable of nothing” (Jn 6:63). Zwingli made it the keystone of his reading: Jesus himself would be cancelling everything he has just said about his flesh to be eaten. But the reading does not hold.

First, if “the flesh is capable of nothing” meant that the flesh of Christ is useless, the whole of Christianity would collapse: the Incarnation, the Cross, the Resurrection in the flesh would be vain. Yet John writes precisely that “the Word became flesh” (Jn 1:14). Jesus cannot declare his own flesh useless five chapters later^[12].

Second, in Johannine and Pauline vocabulary, “the flesh” (as opposed to “the spirit”) does not designate matter or the body, but man left to his merely natural powers, unable to grasp divine realities. “To judge according to the flesh” is to judge in a purely human way (Jn 8:15). The meaning is therefore: understood with the sole resources of the flesh, my words scandalize you; it is the Spirit who will enable you to receive them. Far from denying the realism, the verse explains why that realism demands faith^[13].

On the evening of Holy Thursday, what Jesus had announced at Capernaum, he accomplishes. The four narratives of the institution — Matthew, Mark, Luke and Saint Paul — all use the same formula, of brutal realism:

“Now as they were eating, Jesus took bread, and blessed, and broke it, and gave it to the disciples and said, ‘Take, eat; this is my body.’ And he took a cup, and when he had given thanks he gave it to them, saying, ‘Drink of it, all of you; for this is my blood of the covenant, which is poured out for many for the forgiveness of sins.’” — Gospel according to Saint Matthew 26:26-28^[14]

“Is” and not “represents”

Jesus has a whole vocabulary for expressing symbol at his disposal had he wished. In Aramaic as in Greek, he could have said “this will remind you of my body,” “do this as a sign of me.” He does not say that. He says “is” (estin), and he adds “given for you,” “poured out for the multitude”: not the language of a mere remembrance, but that of a sacrificial memorial — for he also commands “do this in remembrance of me” (Lk 22:19; 1 Cor 11:24-25). That the blood is said to be “poured out” at the very moment of the Supper, before the Cross, shows that the sacrifice is already rendered sacramentally present there^[15].

The classic objection — “Jesus also says ‘I am the door,’ ‘I am the vine’: these are metaphors” — runs up against the context. When Jesus says “I am the vine,” he visibly remains himself, and the vine is manifestly an image of him. But when he holds out a piece of bread saying “this is my body,” he identifies with his “given” body an object distinct from himself, at the close of a discourse in which he maintained his realistic statement to the point of letting disciples leave. Pointing to a distinct object does not, grammatically, rule out every metaphor or metonymy — Saint Paul does write that “this cup is the new covenant in my blood” (1 Cor 11:25) — but the overall context of the Supper and the constant reading of the Church, massive from the first centuries, point toward the realistic sense (see below).

The Marburg Colloquy (1529): when the Reformers divide

This realism is so pronounced in the text that Martin Luther himself refused to let it go. In October 1529, at Marburg, Luther and Zwingli attempted to seal Protestant unity. The fifteen signed articles record the agreement of both parties on the essentials of the faith — and, on the Supper itself, on several points: celebration under both kinds, refusal to make the Mass a meritorious work, divine institution of the sacrament, necessity of spiritual communion. The disagreement, recorded in article 15, concerns solely the bodily presence of the true body and true blood of Christ in the bread and wine, both parties pledging to one another Christian charity despite this difference. According to the report of Andreas Osiander, present at the colloquy, Luther is said to have chalked before him on the table the words “Hoc est corpus meum” (“This is my body”), refusing to read “signifies” into them; Zwingli maintained that “is” meant “signifies” and brandished John 6:63^[16]. The failure thus concerns this precise point — not every understanding: the first fourteen articles were signed on both sides.

The episode is illuminating for our question: the principal adversary of Rome in the sixteenth century held the “is” to be too plain to be reduced to a symbol. The purely symbolist reading did not even command unanimity among the Reformers.

The oldest written testimony on the Eucharist is not a Gospel: it is the First Letter to the Corinthians, dictated by Saint Paul around the year 54, some twenty years after the Supper. And Paul speaks of the Eucharist in terms no one could apply to a mere symbol.

1 Corinthians 10: a communion in the body

“The cup of blessing which we bless, is it not a participation in the blood of Christ? The bread which we break, is it not a participation in the body of Christ?” — First Letter to the Corinthians 10:16^[17]

Paul goes on at once to oppose the table of the Lord to the table of demons: one cannot “drink the cup of the Lord and the cup of demons” (1 Cor 10:21). The Catholic reading sees here the logic of sacrificial communion: just as the meals taken from the victims truly united the guests with the altar served (1 Cor 10:18-20), the cup and the Eucharistic bread truly unite with the body and blood of Christ — not as a mere reminder, but as a participation (koinônia).

1 Corinthians 11:27-29: sacrilege makes sense only for a Real Presence

Paul's strongest argument lies elsewhere. He warns the Corinthians who receive without discernment:

“And whoever shall have eaten the bread or drunk the cup of the Lord unworthily will have to answer for the body and blood of the Lord. […] Whoever eats and drinks eats and drinks his own judgment if he does not discern the body of the Lord.” — First Letter to the Corinthians 11:27, 29^[18]

This sentence is, for the Catholic reading, one of the most direct supports of the Real Presence. Paul does not say “guilty toward a symbol of the Lord,” but “guilty toward the body and blood of the Lord” — and he links this fault to quite real chastisements, sickness and death (1 Cor 11:30). Admittedly, striking a sacred sign may aim, through it, at the one it represents; but the gravity Paul attaches to Eucharistic irreverence is fully explained, for Catholics, only if the body and blood of the Lord are truly received there. Memorialism, which sees in it only ordinary bread accompanied by a remembrance, leaves this passage without real scope^[19].

The realistic reading is no medieval invention of Rome. It is attested from the generation following the Apostles, without interruption, in authors from across the Empire — Greek, Latin, Syriac — and with no known Father teaching the mere symbol. It is one of the most massive patristic consensuses there is — which excludes neither the medieval debates on the mode of this presence nor a frontal challenge in the eleventh century (see below).

Saint Ignatius of Antioch (c. 107)

Bishop of Antioch, whom tradition makes a disciple of the apostle John, led to Rome to be thrown to the beasts, Ignatius writes on the way. He reproaches the Docetist heretics for shunning the Eucharist precisely because they deny the reality of Christ's flesh:

“They abstain from the Eucharist and from prayer, because they confess not the Eucharist to be the flesh of our Saviour Jesus Christ, which suffered for our sins, and which the Father, of His goodness, raised up again.” — Saint Ignatius of Antioch, Letter to the Smyrnaeans, 7:1, c. 107^[20]

Saint Justin Martyr (c. 155)

In his First Apology, addressed to the pagan emperor to explain what Christians really do, Justin describes the Mass and specifies, as early as the mid-second century:

“And this food is called among us ‘Eucharist’ […]. For not as common bread and common drink do we receive these; but in like manner as Jesus Christ our Saviour, having been made flesh by the Word of God, had both flesh and blood for our salvation, so likewise have we been taught that the food which is blessed by the prayer of His word […] is the flesh and blood of that Jesus who was made flesh.” — Saint Justin Martyr, First Apology, 66, c. 155^[21]

Saint Irenaeus of Lyons (c. 180)

Irenaeus argues against the Gnostics: if human flesh could not be saved, the Eucharist would be absurd. His reasoning obviously presupposes that the bread truly becomes the body of Christ:

“The bread, which is produced from the earth, when it receives the invocation of God, is no longer common bread, but the Eucharist, consisting of two realities, earthly and heavenly.” — Saint Irenaeus of Lyons, Against Heresies, IV, 18:5, c. 180^[22]

Saint Cyril of Jerusalem (c. 350)

In his Mystagogical Catecheses, addressed to the newly baptized, Cyril warns them against the judgment of the senses — an argument Saint Thomas Aquinas will take up:

“Do not, therefore, regard the bread and wine as simply that; for they are, according to the Master's declaration, the Body and Blood of Christ. Even though the senses suggest that to you, let faith make you firm. Do not judge in this matter by taste, but be fully assured by faith, not doubting that you have been deemed worthy of the Body and Blood of Christ.” — Saint Cyril of Jerusalem, Mystagogical Catecheses, IV, 6, c. 350^[23]

Saint John Chrysostom (c. 390)

The great preacher of Antioch and then of Constantinople, surnamed “Golden Mouth,” preaches an ardent Eucharistic realism:

“It is not man that causes the things offered to become the Body and Blood of Christ, but he who was crucified for us, Christ himself. The priest stands there carrying out the action, but it is the power and grace of God that act. ‘This is my body,’ he says. This word transforms the things offered.” — Saint John Chrysostom, Homily on the Treachery of Judas, 1:6, c. 390^[24]

The case of Saint Augustine: the alleged “symbolist”

Defenders of memorialism readily cite Saint Augustine (354-430), who stresses the “sign” dimension of the sacrament and coins formulas such as “believe, and you have eaten” (Tractates on the Gospel of John, XXV, 12). Making him a symbolist before his time is nevertheless a misconstrual. Augustine distinguishes the signum (the sensible sign) from the res (the reality contained) — but for him the sign contains and gives what it signifies; it does not replace it. The same Augustine writes, commenting on Psalm 33, this sentence no symbolist could utter:

“‘He was borne in His own hands’ […]: how can this be done by a man? […] Christ, for His part, was borne in His own hands when, presenting His own body, He said, ‘This is my body’ — for He bore that body in His hands.” — Saint Augustine, Exposition of Psalm 33, sermon I, 10, c. 400^[25] (abbreviated quotation; Ignispedia translation)

Augustine also exhorts his faithful: “No one eats that flesh unless he has first adored it […] ; we would sin were we not to adore it.”^[26] One does not adore a symbol. Augustine's realism is spiritual and demanding, but real: his theology of the sign is that of the Catholic sacrament, not that of Zwingli.

The massive historical fact is therefore this: for nearly a thousand years, the realistic faith dominates without known rival — in the West, at Byzantium as in the Syriac, Coptic or Armenian East — and the Eastern Churches profess to this day that bread and wine truly become the body and blood of Christ^[27]. This continuity excludes neither the medieval debates on the mode of the presence, nor the frontal challenge of Berengar in the eleventh century (see below), nor that of a fringe of the Reformation in the sixteenth: but it is the challenge that is late, not the doctrine.

The eleventh century sees the first frontal internal challenge arise. Berengar of Tours (c. 999-1088), schoolman — master of the cathedral school — of Tours, maintained that bread and wine are only a “sign” (figura) of Christ's body, present merely in a spiritual manner. His thesis caused scandal precisely because it was perceived as a novelty contrary to the received faith. Condemned by several councils, Berengar ended by retracting. Not to be confused with the Carolingian debates of the ninth century: the exchange between Paschasius Radbertus and Ratramnus of Corbie concerned the manner of understanding this presence, within a framework that remained realistic — a school question of another order than the Berengarian crisis. In 1079, before a Roman synod, he signed a profession of faith that has remained famous:

“I believe in my heart and confess with my mouth that the bread and wine placed on the altar are, through the mystery of the sacred prayer and the words of our Redeemer, substantially changed into the true, proper and life-giving flesh and blood of our Lord Jesus Christ.” — Profession of faith of Berengar of Tours, Synod of Rome, 1079^[28]

This episode is doubly instructive. On the one hand, it confirms that the realistic faith was indeed the norm: it is Berengar who innovates, and it is he who must retract. On the other, the crisis pushes the Church to clarify her vocabulary. The word transubstantiation appears in the following decades and is taken up by the Fourth Lateran Council in 1215^[29]. It does not create a new doctrine; it gives a technical name to the faith that Ignatius, Justin and Cyril already professed.

When the Reformation frontally contests the Real Presence, the Church answers with a solemn definition. The Council of Trent, in its Session XIII (11 October 1551), publishes the Decree on the Most Holy Sacrament of the Eucharist. It is the text that explicitly condemns, and for the first time with such precision, the “merely a symbol” thesis.

Canon 1: “not only in a sign or figure”

The first canon targets memorialism word for word:

“If any one denieth, that, in the sacrament of the most holy Eucharist, are contained truly, really, and substantially, the body and blood together with the soul and divinity of our Lord Jesus Christ, and consequently the whole Christ; but saith that He is only therein as in a sign, or in figure, or virtue; let him be anathema.” — Council of Trent, Session XIII, canon 1, 1551^[30]

The exact text of the canon reads: “sed dixerit tantummodo esse in eo ut in signo vel figura aut virtute” — “but saith that He is only therein as in a sign, or in figure, or virtue”: it is this “only” (tantummodo) that the council condemns. In other words, and to sum up the meaning: not only in a sign or a figure. Catholicism does not deny that the Eucharist is a sign; it denies that it is “only” that. (Anathema: solemn exclusion from the communion of the Church, pronounced here against the condemned doctrine.)

Transubstantiation: the word that says the real

Chapter 4 of the same decree explains the change with the notion of substance:

“By the consecration of the bread and wine there takes place a change of the whole substance of the bread into the substance of the body of Christ our Lord and of the whole substance of the wine into the substance of his blood. This change the holy Catholic Church has fittingly and properly called transubstantiation.” — Council of Trent, Session XIII, ch. 4, 1551^[31]

What the senses continue to perceive — the color, taste and shape of bread — the Church calls the “species” or “appearances.” They truly remain, but what they veil has changed. The how of this change is treated in the article What is transubstantiation?.

Faith in the Real Presence raises recurring objections. None is new; all received an answer from the Fathers or Saint Thomas Aquinas onward.

“Jesus was speaking metaphorically, as in ‘I am the door’”

Answer already given above: the context differs. In a metaphor, the subject manifestly remains itself (Jesus saying “I am the vine” remains Jesus, visibly). In the institution, Jesus identifies with his “given” body an object distinct from himself — the bread — at the close of a discourse in which he maintained his realistic statement to the point of letting disciples leave (Jn 6:60-67). The metaphorical reading remains grammatically possible, but it must reckon with the Capernaum scene: it is that scene, with the constant reading of the Church, which tips the balance toward the realistic sense.

“The flesh is capable of nothing; only the spirit counts” (Jn 6:63)

Already treated: “the flesh” here designates man left to his own powers, not the flesh of Christ, which has just been declared “true food.” On the Catholic reading, then, this verse does not deny realism: it teaches that realism is received only in the Spirit and in faith — the Real Presence is apprehended only by faith, as the Catechism recalls^[32].

“The senses perceive only bread”

That is true — and it is precisely the heart of the mystery, not an objection against it. Cyril of Jerusalem already warned: “Do not judge by taste, but by faith.” The hymn Adoro te devote, attributed to Saint Thomas Aquinas, sings it thus:

“Seeing, touching, tasting are in thee deceived; but hearing suffices firmly to believe. I believe all the Son of God has spoken; than Truth's own word there is no truer token.” — Saint Thomas Aquinas, hymn Adoro te devote, c. 1264^[33]

Faith does not contradict the senses: it surpasses them where they cannot reach. The senses correctly perceive the appearances; they cannot reach the substance, which belongs to the intellect and, here, to revelation.

“It is cannibalism”

The objection supposes that we eat Christ as one would eat any flesh — cut up, diminished, consumed. But Christ is present “after the manner of substance,” not as a localized body that could be diminished: he is present whole under each species and under each fragment, without being divided, in his glorious risen body which can no longer suffer or die^[34]. We do not “digest” Christ; it is he who assimilates us to himself. Saint Augustine has him say: “Thou shalt not change me into thee as the food of thy flesh, but thou shalt be changed into me.”^[35]

“The idea is late, invented in the Middle Ages”

The reverse is true. The word transubstantiation is medieval, but the thing — the Real Presence of the body and blood — is attested from Ignatius of Antioch (c. 107), before the canon of the New Testament was even fixed. It is the challenges (Berengar, then the Reformation) that are late, not the doctrine. A belief attested from the second century in Fathers from across the Empire, in the ancient liturgies, cannot have been “invented” in the thirteenth.

This question is not speculative: it decides a whole Christian life. If Christ is truly present, then a whole series of Catholic practices become not only legitimate but obvious.

Adore, reserve, visit

Because Christ remains present as long as the species subsist, the Church reserves the consecrated hosts in the tabernacle, keeps a lamp burning there, kneels before them, exposes them for adoration, carries them in procession at Corpus Christi. All these practices would be absurd, even idolatrous, before a mere symbol; they are the exact consequence of the realistic faith. That is also why the Church asks the faithful not to receive Communion in a state of grave sin without first going to confession: one does not receive the Lord himself just anyhow (see May one receive Communion in a state of mortal sin?).

Eucharistic miracles

The history of the Church preserves dossiers of this kind, distinct and unequally documented: Lanciano, whose event tradition traces back to the eighth century, and Buenos Aires — notably the host of 1996 kept in the church of Santa María (the dossiers distinguish the events of 1992, 1994 and 1996). The Church does not ground her faith on them, but they illustrate it. They are examined in the article Eucharistic miracles and Sanctuary of Lanciano, without prejudging here any status of recognition.

“The center of existence”

There remains the simplest testimony. If the Eucharist is only a symbol, it deserves the respect owed to a fine devotional image — nothing more. If it is Christ, then it is, in Flannery O'Connor's words, “the center of existence,” and everything else becomes secondary. That is also what the Second Vatican Council says in calling the Eucharist “the source and summit of the whole Christian life”^[36]. The stakes of the question “merely a symbol?” are therefore not doctrinal in the cold sense of the term: it is a matter of knowing whether, at the tabernacle, someone is waiting.

• The Real Presence in the Eucharist — the complete doctrinal exposition of what this article summarizes
• What is transubstantiation? — the how of the change of substance
• Why is the Eucharist a sacrifice? — the sacrificial dimension of the Mass
• What is a sacrament? — the sign that effects what it signifies
• May one receive Communion in a state of mortal sin?
• Eucharistic miracles — Lanciano, Bolsena, Buenos Aires
• Corpus Christi
• Why is Sunday Mass obligatory?
• Answers to Protestantism