What are the differences between the Lutheran and Reformed positions on the Lord’s Supper?  Do you know?  If you talk to Lutherans or people influenced by the Calvinist wing of the reformation, you should.  I would also commend to you the pamphlets Bible Truths for Lutheran Friends and The Reformed Doctrine of Salvation to give to Lutherans and Reformed people to whom you preach the gospel, or with whom you work, or who are family, and so on.

The dialogue below between Luther, Zwingle, and a few other theologians who take their (respective) parts should be enlightening.  Luther firmly holds that “This is my body” means that one literally eats Christ’s body in the Lord’s Supper, while Zwingle argues that one eats Christ spiritually in the Supper.  The excerpt below is about the Marburg Colloquy of October 1529, quoting H. Merle D’Aubigné, History of the Reformation in the Sixteenth Century:

On Saturday morning (2d October) the landgrave took his seat in the hall, surrounded by his court, but in so plain a dress that no one would have taken him for a prince. He wished to avoid all appearance of acting the part of a Constantine in the affairs of the Church. Before him was a table which Luther, Zwingle, Melancthon, and Œcolampadius approached. Luther, taking a piece of chalk, bent over the velvet cloth which covered it, and steadily wrote four words in large characters. All eyes followed the movement of his hand, and soon they read Hoc est Corpus Meum. [“This is my body.”] Luther wished to have this declaration continually before him, that it might strengthen his own faith, and be a sign to his adversaries.

Behind these four theologians were seated their friends,—Hedio, Sturm, Funck, Frey, Eberhard, Thane, Jonas, Cruciger, and others besides. Jonas cast an inquiring glance upon the Swiss: “Zwingle,” said he, “has a certain rusticity and arrogance; if he is well versed in letters, it is in spite of Minerva and of the muses. In Œcolampadius there is a natural goodness and admirable meekness. Hedio seems to have as much liberality as kindness; but Bucer possesses the cunning of a fox, that knows how to give himself an air of sense and prudence.” Men of moderate sentiments often meet with worse treatment than those of the extreme parties. … 

The landgrave’s chancellor, John Feige, having reminded them in the prince’s name that the object of this colloquy was the re-establishment of union, “I protest,” said Luther, “that I differ from my adversaries with regard to the doctrine of the Lord’s Supper, and that I shall always differ from them. Christ has said, This is my body. Let them show me that a body is not a body. I reject reason, common sense, carnal arguments, and mathematical proofs. God is above mathematics. We have the Word of God; we must adore it and perform it!”

It cannot be denied,” said Œcolampadius, “that there are figures of speech in the Word of God; as John is Elias, the rock was Christ, I am the vine. The expression This is my body, is a figure of the same kind.” Luther granted that there were figures in the Bible, but denied that this last expression was figurative.

All the various parties, however, of which the Christian Church is composed see a figure in these words. In fact, the Romanists declare that This is my body signifies not only “my body,” but also “my blood,” “my soul,” and even “my Divinity,” and “Christ wholly.” These words, therefore according to Rome, are a synecdoche, a figure by which a part is taken for the whole. And, as regards the Lutherans, the figure is still more evident. Whether it be synecdoche, metaphor, or metonymy, there is still a figure.

In order to prove it, Œcolampadius employed this syllogism:—

“What Christ rejected in the sixth chapter of St. John, he could not admit in the words of the Eucharist.

“Now Christ, who said to the people of Capernaum, The flesh profiteth nothing, rejected by those very words the oral manducation of his body.

“Therefore he did not establish it at the institution of his Supper.”

Luther.—“I deny the minor (the second of these propositions); Christ has not rejected all oral manducation, but only a material manducation, like that of the flesh of oxen or of swine.”

Œcolampadius.—“There is danger in attributing too much to mere matter.”

Luther.—“Everything that God commands becomes spirit and life. If we lift up a straw, by the Lord’s order, in that very action we perform a spiritual work. We must pay attention to him who speaks, and not to what he says. God speaks: Men, worms, listen!—God commands: let the world obey! and let us altogether fall down and humbly kiss the Word.”

Œcolampadius.—“But since we have the spiritual eating, what need of the bodily one?”

Luther.—“I do not ask what need we have of it; but I see it written, Eat, this is my body. We must therefore believe and do. We must do—we must do!—If God should order me to eat dung, I would do it, with the assurance that it would be salutary.”

At this point Zwingle interfered in the discussion.

We must explain Scripture by Scripture,” said he, “We cannot admit two kinds of corporeal manducation, as if Jesus had spoken of eating, and the Capernaites of tearing in pieces, for the same word is employed in both cases. Jesus says that to eat his flesh corporeally profiteth nothing (John, 6:63); whence it would result that he had given us in the Supper a thing that would be useless to us.—Besides, there are certain words that seem to me rather childish,—the dung, for instance. The oracles of the demons were obscure, not so are those of Jesus Christ.”

Luther.—“When Christ says the flesh profiteth nothing, he speaks not of his own flesh, but of ours.”

Zwingle.—“The soul is fed with the Spirit and not with the flesh.”

Luther.—“It is with the mouth that we eat the body; the soul does not eat it.”

Zwingle.—“Christ’s body is therefore a corporeal nourishment, and not a spiritual.”

Luther.—“You are captious.”

Zwingle.—“Not so; but you utter contradictory things.”

Luther.—“If God should present me wild apples, I should eat them spiritually. In the Eucharist, the mouth receives the body of Christ, and the soul believes in his words.”

Zwingle then quoted a great number of passages from the Holy Scriptures, in which the sign is described by the very thing signified; and thence concluded that, considering our Lord’s declaration in St. John, The flesh profiteth nothing, we must explain the words of the Eucharist in a similar manner.

Many hearers were struck by these arguments. Among the Marburg professors sat the Frenchman Lambert; his tail and spare frame was violently agitated. He had been at first of Luther’s opinion, and was then hesitating between the two reformers. As he went to the conference, he said: “I desire to be a sheet of blank paper, on which the finger of God may write his truth.” Erelong he exclaimed, after hearing Zwingle and Œcolampadius: “Yes! the Spirit, ’tis that which vivifies.” When this conversion was known, the Wittembergers, shrugging their shoulders, called it “Gallic fickleness.” “What!” replied Lambert, “was St. Paul fickle because he was converted from Pharisaism? And have we ourselves been fickle in abandoning the lost sects of popery?”

–TDR