Why Do Catholics Believe the Eucharist is Really Jesus’s Actual Body & Blood?

Protestant attacks on the Catholic Church often focus on the Eucharist. This demonstrates that opponents of the Church—mainly Evangelicals and Fundamentalists—recognize one of Catholicism’s core doctrines. What’s more, the attacks show that Fundamentalists are not always literalists. This is seen in their interpretation of the key biblical passage, chapter six of John’s Gospel, in which Christ speaks about the sacrament that will be instituted at the Last Supper. In this essay, we will examine the last half of that chapter.

John 6:30 begins a colloquy that took place in the synagogue at Capernaum. The Jews asked Jesus what sign he could perform so that they might believe in him. As a challenge, they noted that “our fathers did eat manna in the desert.” Could Jesus top that? He told them the real bread from heaven comes from the Father. “Give us always this bread,” they said. Jesus replied, “I am the bread of life: he that cometh to me shall not hunger: and he that believeth in me shall never thirst.” At this point the Jews understood him to be speaking metaphorically.

Jesus first repeated what he said, then summarized: “I am the living bread which came down from heaven. If any man eat of this bread, he shall live for ever; and the bread that I will give, is my flesh, for the life of the world. The Jews therefore strove among themselves, saying: How can this man give us his flesh to eat?”

His listeners were stupefied because now they understood Jesus literally—and correctly. He again repeated his words, but with even greater emphasis, and introduced the statement about drinking his blood: “Amen, amen I say unto you: Except you eat the flesh of the Son of man, and drink his blood, you shall not have life in you. He that eateth my flesh, and drinketh my blood, hath everlasting life: and I will raise him up in the last day. For my flesh is meat indeed: and my blood is drink indeed. He that eateth my flesh, and drinketh my blood, abideth in me, and I in him.”

Notice that Jesus made no attempt to soften what he said, no attempt to correct “misunderstandings,” for there were none. Our Lord’s listeners understood him perfectly well. They no longer thought he was speaking metaphorically. If they had, if they mistook what he said, why no correction?

On other occasions when there was confusion, Christ explained just what he meant (cf. Matt. 16:5-12). Here, where any misunderstanding would be fatal, there was no effort by Jesus to correct. Instead, he repeated himself for greater emphasis.

In John 6:61 we read: “Many therefore of his disciples, hearing it, said: This saying is hard, and who can hear it?” These were his disciples, people used to his remarkable ways. He warned them not to think carnally, but spiritually: “It is the spirit that quickeneth: the flesh profiteth nothing. The words that I have spoken to you, are spirit and life.” (John 6:64; cf. 1 Cor. 2:12-14).

But he knew some did not believe. (It is here, in the rejection of the Eucharist, that Judas fell away; look at John 6:64.) “After this many of his disciples went back; and walked no more with him.”

This is the only record we have of any of Christ’s followers forsaking him for purely doctrinal reasons. If it had all been a misunderstanding, if they erred in taking a metaphor in a literal sense, why didn’t he call them back and straighten things out? Both the Jews, who were suspicious of him, and his disciples, who had accepted everything up to this point, would have remained with him had he said he was speaking only symbolically.

But he did not correct these protesters. Twelve times he said he was the bread that came down from heaven; four times he said they would have “to eat my flesh and drink my blood.” John 6 was an extended promise of what would be instituted at the Last Supper, and it was a promise that could not be more explicit. Or so it would seem to a Catholic. But what do Fundamentalists say?

They say that in John 6 Jesus was not talking about physical food and drink, but about spiritual food and drink. They quote John 6:35: “Jesus said to them: I am the bread of life: he that cometh to me shall not hunger: and he that believeth in me shall never thirst.” They claim that coming to him is bread, having faith in him is drink. Thus, eating his flesh and blood merely means believing in Christ.

But there is a problem with that interpretation. As Fr. John A. O’Brien explains, “The phrase ‘to eat the flesh and drink the blood,’ when used figuratively among the Jews, as among the Arabs of today, meant to inflict upon a person some serious injury, especially by calumny or by false accusation. To interpret the phrase figuratively then would be to make our Lord promise life everlasting to the culprit for slandering and hating him, which would reduce the whole passage to utter nonsense” (O’Brien, The Faith of Millions, 215). For an example of this use, see Micah 3:3.

Fundamentalist writers who comment on John 6 also assert that one can show Christ was speaking only metaphorically by comparing verses like John 10:9 (“I am the door”) and John 15:1 (“I am the true vine”). The problem is that there is not a connection to John 6:35, “I am the bread of life.” “I am the door” and “I am the vine” make sense as metaphors because Christ is like a door—we go to heaven through him—and he is also like a vine: we get our spiritual sap through him. But Christ takes John 6:35 far beyond symbolism by saying at John 6:56, “For my flesh is meat indeed: and my blood is drink indeed.”

He continues: “He that eateth my flesh, and drinketh my blood, abideth in me, and I in him.” The Greek word used for “eats” (trogo) is very blunt and has the sense of “chewing” or “gnawing.” This is not the language of metaphor.

For Fundamentalist writers, the scriptural argument is capped by an appeal to John 6:64: “It is the spirit that quickeneth: the flesh profiteth nothing. The words that I have spoken to you, are spirit and life.” They say this means that eating real flesh is a waste. But does this make sense?

Are we to understand that Christ had just commanded his disciples to eat his flesh, then said their doing so would be pointless? Is that what “the flesh is of no avail” means? “Eat my flesh, but you’ll find it’s a waste of time”—is that what he was saying? Hardly.

The fact is that Christ’s flesh avails much! If it were of no avail, then the Son of God incarnated for no reason, he died for no reason, and he rose from the dead for no reason. Christ’s flesh profits us more than anyone else’s in the world. If it profits us nothing, so that the incarnation, death, and resurrection of Christ are of no avail, then “your faith is futile and you are still in your sins. Then those also who have fallen asleep in Christ have perished” (1 Cor. 15:17-18).

In John 6:64 “flesh profiteth nothing” refers to mankind’s inclination to think using only what their natural human reason would tell them rather than what God would tell them. Thus in John 8:15-16 Jesus tells his opponents: “You judge according to the flesh: I judge not any man. And if I do judge, my judgment is true: because I am not alone, but I and the Father that sent me.” So natural human judgment, unaided by God’s grace, is unreliable; but God’s judgment is always true.

And were the disciples to understand the line “The words I have spoken to you are spirit and life” as nothing but a circumlocution (and a very clumsy one at that) for “symbolic“? No one can come up with such interpretations unless he first holds to the Fundamentalist position and thinks it necessary to find a rationale, no matter how forced, for evading the Catholic interpretation. In John 6:64 “flesh” does not refer to Christ’s own flesh (the context makes this clear) but to mankind’s inclination to think on a natural, human level. “The words I have spoken to you are spirit” does not mean “What I have just said is symbolic.” The word “spirit” is never used that way in the Bible. The line means that what Christ has said will be understood only through faith; only by the power of the Spirit and the drawing of the Father (cf. John 6:37, 44-45, 65).

Paul wrote to the Corinthians: “The chalice of benediction, which we bless, is it not the communion of the blood of Christ? And the bread, which we break, is it not the partaking of the body of the Lord?” So when we receive Communion, we actually participate in the body and blood of Christ, not just eat symbols of them. Paul also said, “Therefore whosoever shall eat this bread, or drink the chalice of the Lord unworthily, shall be guilty of the body and of the blood of the Lord. … For he that eateth and drinketh unworthily, eateth and drinketh judgment to himself, not discerning the body of the Lord.” To be “guilty of the body and of the blood” of someone meant to be guilty of a crime as serious as homicide. How could eating mere bread and wine “unworthily” be so serious? Paul’s comment makes sense only if the bread and wine became the real body and blood of Christ.

Anti-Catholics also claim the early Church took this chapter symbolically. Is that so? Let’s see what some early Christians thought, keeping in mind that we can learn much about how Scripture should be interpreted by examining the writings of early Christians.

Ignatius of Antioch, who had been a disciple of the apostle John and who wrote a letter to the Smyrnaeans about A.D. 110, said, referring to “those who hold heterodox opinions,” that “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.”

Forty years later, Justin Martyr wrote, in his First Apology, “And this food is called among us Εὐχαριστία [the Eucharist], of which no one is allowed to partake but the man who believes that the things which we teach are true, and who has been washed with the washing that is for the remission of sins, and unto regeneration, and who is so living as Christ has enjoined. 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, and from which our blood and flesh by transmutation are nourished, is the flesh and blood of that Jesus who was made flesh.”

Origen, in his Homilies on Exodus, written about A.D. 244, attested to belief in the Real Presence. “I wish to admonish you with examples from your religious practices. You who are accustomed to take part in divine mysteries know, when you receive the body of the Lord, how you protect it with all caution and veneration lest any small part fall from it, lest anything of the consecrated gift be lost. For you believe, and correctly, that you are answerable if anything falls from there by neglect.”

Cyril of Jerusalem, in a catechetical lecture presented in the mid-300s, said, “Contemplate therefore the Bread and Wine not as bare elements, for they are, according to the Lord’s declaration, the Body and Blood of Christ; for though sense suggests this to thee, let faith stablish thee. Judge not the matter from the taste, but from faith be fully assured without misgiving, that thou hast been vouchsafed the Body and Blood of Christ.”

Theodore of Mopsuestia seemed to be speaking to today’s Evangelicals and Fundamentalists when he wrote (in his Commentary on Matthew: “When [Christ] gave the Bread He did not say, ‘This is the symbol of My Body,’ but, ‘This is My Body.’ In the same way, when He gave the Cup He did not say, ‘This is the symbol of My Blood,’ but, ‘This is My Blood,’ for He wanted us to look upon the [Eucharistic elements] after their reception of grace and the coming of the Holy Spirit not according to their nature, but [that we should] receive them as they are, the Body and Blood of our Lord.”

Whatever else might be said, the early Church took John 6 literally. In fact, there is no record from the early centuries that implies Christians doubted the constant Catholic interpretation. There exists no document in which the literal interpretation is opposed and only the metaphorical accepted.

Why do Fundamentalists and Evangelicals reject the plain, literal interpretation of John 6? For them, Catholic sacraments are out because they imply a spiritual reality—grace—being conveyed by means of matter. This seems to them to be a violation of the divine plan. For many Protestants, matter is not to be used, but overcome or avoided.

One suspects, had they been asked by the Creator their opinion of how to bring about mankind’s salvation, Fundamentalists would have advised him to adopt a different approach. How much cleaner things would be if spirit never dirtied itself with matter! But God approves of matter—he approves of it because he created it—and he approves of it so much that he comes to us under the appearances of bread and wine, just as he does in the physical form of the Incarnate Christ.