On the Eucharist: Why can't Protestants receive Catholic Communion?

A friend recently wrote the following on her blog:

"we went to catholic mass on sunday. it was great to be in church, and the priest mentioned a few times the desire for unity among all those who believe in jesus, which is something we all can hope for. but then came communion, and protestants aren't supposed to take catholic communion. it saddened me that i wasn't allowed to take communion, since we believe in the same God, the same body + blood + cross + resurrection. also, to my knowledge, protestants would welcome catholics to take communion in a protestant church. so i'm not sure why the reverse isn't true?"

This post will be my attempt to shed a little light -- however dim -- on the issue for my friend, from a Catholic perspective. I hope it might be helpful or interesting to others, as well.

What is Catholic Communion?

I'll start off by saying that the sacrament of Communion, or the Eucharist, is something far more profound than most people -- Catholic, Protestant, or otherwise -- realize. I won't pretend to have a complete, or even an adequate, understanding of the Eucharist, either intellectually or spiritually. But I'll do my best to explain what little I can as clearly as I can.

Most people just can't accept the fundamental Catholic teaching about the Eucharist, but here's what it boils down to: The Eucharist is Jesus.

That little disk that looks, smells, feels, tastes exactly like a bland wheat cracker, that liquid in the chalice that sure seems like wine, actually is the Body, Blood, Soul, and Divinity of the Second Person of the Trinity. Not just symbolically. It really is Jesus -- God -- in the most real, full, and immediate manifestation of Himself that we can experience in this life.

To get philosophical about it, the sacrament of the Eucharist involves "transubstantiation," meaning that the substance, or essence, of the bread and wine changes -- in a real, fundamental, ontological way -- into the substance of the Body and Blood of Jesus, while the accidents/appearances/characteristics -- those things that can be observed with the senses -- of bread and wine remain.

The word transubstantiation means that this change of substance is complete: The Body and Blood of Christ are not contained in the bread and wine, nor do they exist side by side with the bread and wine. The bread and wine are gone, completely replaced by the Body and Blood of Jesus.

That the accidents of bread and wine remain means that if you were to hold up a consecrated ("transubstantiated") Host next to an unconsecrated one -- in other words, if you were to hold the Eucharist in one hand and an ordinary wheaten wafer in the other -- you would not detect the slightest difference between them. If you put them under a microscope, they'd look exactly the same. They'd taste the same, too. No matter what scientific scrutiny you subjected them to, you wouldn't find any discrepancy between them.

But one would be a cracker, and the other would be the Savior of the world.

This miraculous transubstantiation takes place when, during the Mass, the priest holds the wheat bread and grape wine and says the words of institution that Jesus spoke at the Last Supper ("This is my body" and "This is my blood"). By the power of Jesus' words and the Holy Spirit, the bread and wine truly become the Body, Blood, Soul, and Divinity of Christ, and Jesus' once-for-all sacrifice on the Cross is made present on the altar. At the Mass, we are thus present in a mystical but very real way both at the Last Supper and at Jesus' Crucifixion.

The Church refers to the Eucharist as "the source and summit of the Christian life." It is a conduit of grace -- the very life of God -- for our souls. It is the greatest gift God could possibly give His Church, because it is the gift of God's very Self. For that reason, when the priest elevates the consecrated Host and the chalice of the precious Blood, we can -- and in justice must -- worship it and in our hearts exclaim, "My Lord and my God!"

Why do Catholics believe all this?

Now, if this all sounds completely ridiculous, or if you're thinking that I must not really be saying what it sounds like I'm saying, that I couldn't possibly believe that I'm literally consuming God when I go to Mass each week, then you're experiencing much the same reaction that Jesus' disciples had the first time He foretold the institution of the Eucharist, when He told a crowd, "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" (John 6:51).

Naturally, this didn't make a lot of sense to His hearers, who obviously took Him quite literally: "How can this man give us his flesh to eat?" (John 6:52) they asked each other. Now, Jesus had run into problems before with His disciples taking Him literally when He was merely speaking figuratively (see Matthew 16:6-12 and John 4:31-34). In such cases, He was always quick to clear up the misunderstanding.

But in this instance, Jesus reiterated His shocking message even more emphatically: "Truly, truly, I say to you, unless you eat the flesh of the Son of man and drink his blood, you have no life in you; he who eats my flesh and drinks my blood has eternal life, and I will raise him up at the last day. For my flesh is food indeed, and my blood is drink indeed" (John 6:53-55).

At this point, many of Jesus' disciples said, "This is a hard saying; who can listen to it?" (John 6:60) and walked away. But Jesus didn't call after them, "Wait, come back! I was just speaking metaphorically!" Why? Because He was being cruel and deceptive? Or because He hadn't been speaking metaphorically?

We find the same kind of literal language in the accounts of the Last Supper, when Jesus instituted the sacrament of the Eucharist. Luke records it this way: "And he took bread, and when he had given thanks he broke it and gave it to them, saying, 'This is my body which is given for you. Do this in remembrance of me.' And likewise the cup after supper, saying, 'This cup which is poured out for you is the new covenant in my blood'" (Luke 22:19-20). The same God Who spoke all of creation into existence declared bread to be His Body, and so it was. (Those words, "Do this in remembrance of me," by the way, are where the Church finds the institution of its sacramental priesthood.)

That the apostles understood Jesus to be speaking literally at the Last Supper is evident from the testimony of the early Church, which was taught by the apostles. Ignatius of Antioch, a bishop who was martyred for the faith in the early 100s, and who was himself a disciple of the apostle John, wrote to the Church in Smyrna about "those who hold heterodox opinions" that "[t]hey abstain from the Eucharist and from prayer, because they do not confess that the Eucharist is the Flesh of our Savior Jesus Christ, Flesh which suffered for our sins and which the Father, in His Goodness, raised up again."

For 2,000 years, the Catholic Church has trusted in Jesus' words at the Last Supper. She has celebrated the Eucharist as the very center of the Church's life and has maintained a steadfast faith in the life-giving reality of Christ's real presence in the Eucharist.

Why can't Protestants receive Catholic Communion?

So, after that long introduction (which, believe it or not, barely scratches the surface of the Church's rich and polyvalent understanding of the sacrament), we actually get to the question we started with: Why can't Protestants receive Communion in the Catholic Church? As this question was posed in the context of a desire for Christian unity, I'll try to address that issue as well.

The Catholic Church longs for Jesus' prayer "that they may all be one" (John 17:21) to be fulfilled, and is grieved by the fact of division within the Body of Christ, because division is contrary to the will of Christ, Who is the Head of the Church.

Since the Catholic Church understands herself to be, historically, the one Church that Jesus founded, she sees herself as the locus of Christian unity and prays that all people might be reconciled to her and, through her, to Christ. Which means, to put it bluntly, that the Catholic Church desires, ultimately, for all people to become Catholic.

Doesn't that make the Catholic Church the most delusionally presumptuous and hubristic organization on the planet? Yes it does, if the Church's desire is not also the will of God. But that's a topic for another excessively long essay.

Does this desire mean that the Catholic Church does not regard Protestants as true Christians? By no means! The Church regards all those who have been baptized as brothers and sisters in Christ and recognizes that God is truly at work in Protestant communities.

But while the Church sees non-Catholic Christians as brothers and sisters in Christ, she must honestly acknowledge that they are "separated brethren." While the Catholic Church longs, works, and prays for full unity in the Body of Christ, the wounds of division cannot be healed by fiat. While great strides have been made in mutual understanding and reconciliation between Catholic and non-Catholic Christians in recent decades, the longed-for unity is not yet a reality.

The Eucharist is a sacrament of unity: It both signifies and strengthens the bonds of unity within the Church. You might ask why, if the Eucharist is a source of unity, Catholics wouldn't encourage Protestants to receive Catholic Communion, so that the divisions in the Body of Christ might be healed. The answer to that question can be found in Paul's first letter to the Corinthians. After recounting Jesus' words at the Last Supper, Paul writes:

"Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of profaning the body and blood of the Lord. Let a man examine himself, and so eat of the bread and drink of the cup. For any one who eats and drinks without discerning the body eats and drinks judgment upon himself. That is why many of you are weak and ill, and some have died." (1 Corinthians 11:27-30)

Serious stuff. And so the Catholic Church's teaching that Protestants -- who typically do not discern the Body and Blood of Christ in the Eucharist in the same way that the Catholic Church does -- ought not receive Catholic Communion is born, not out of some ill-conceived and insensitive desire for exclusivity, but primarily out of love. Undoubtedly it can be hard to feel the love when you're the only one left sitting in the pews at Communion time, but love really is the motive.

The passage from 1 Corinthians also highlights another Church teaching about the Eucharist which is rarely emphasized or even acknowledged these days: Catholics are not to receive the Eucharist if they are conscious of having committed any serious sins which they have not confessed in the sacrament of reconciliation. To receive the Eucharist in such a state of sin is, itself, a serious sin. Protestants are not the only ones who ought not receive the Eucharist at Mass. There are, in all likelihood, several Catholics eating and drinking judgment upon themselves at most Masses by receiving the Eucharist in an unworthy manner (I have, unfortunately, often been one of them in the past), and we are not to be envied.

There is more that I could say -- and much, much more that could be said -- about the Eucharist, but this post has gone on long enough.

If you have any questions or want to take issue with anything I've written, please feel free to leave a comment or send me an e-mail, and I will do my best to respond.

And if you want more complete and authoritative information about the Eucharist than I can offer, please check out the Catechism of the Catholic Church or, for a briefer treatment, the Compendium of the Catechism of the Catholic Church.