There are two men to whom Reformed churches and believers owe gratitude for their doctrine of the sacraments: Martin Luther and John Calvin. The debt of gratitude owed to Calvin is obvious. It is not so clear that Luther must be thanked. There cannot be serious thanks given for the Reformation’s recovery of the gospel of the sacraments, however, without noticing Calvin and Luther.1

This is especially true with regard to the contentious doctrine of the Lord’s supper. The controversy rocked the European continent during the Reformation. Furious exchanges of tracts, treatises, and letters, and intense face-to-face discussions did not resolve the issue. In the middle of—and driving—the doctrinal maelstrom was Martin Luther.

Luther wrote voluminously on the Lord’s supper—twelve major works from 1519 to 1544—in addition to preaching many sermons on the subject.

In his first extended treatment of the sacraments in 1520, The Babylonian Captivity of the Church, he criticized the Roman Catholic sacramental system of grace dispensed through sacraments that covered a man’s life from cradle to grave. Luther rejected Rome’s seven sacraments and taught that Christ instituted only two sacraments, the Lord’s supper and baptism. All of the Reformers agreed. They also agreed with his rejection of the mass as a sacrifice, private masses for the living and the dead, and the mass as a meritorious work. Luther objected, as did the other Reformers, to the doctrine of transubstantiation, which teaches that the priest turns the bread and wine into the body and blood of Christ. But Luther did not and never would reject the idea, taught in one form by Rome, that Christ was physically present and eaten in the Lord’s supper.

He defended his position in a book whose title captures his essential doctrine, “That These Words of Christ: This is My Body, etc. Stand Firm Against the Fanatics, 1527. He based his doctrine on the words of institution:

Now, to come to grips with the subject, let us take up the saying of Christ…“he took bread, and gave thanks, and broke it, and gave it to his disciples and said, ‘Take, eat; this is my body which is given for you’” (Robinson, 183).

Luther insisted that the words of institution—this is my body—mean exactly what they say: “Now, here stands the text, stating clearly and lucidly, that Christ gives his body to us when he distributes the bread” (Robinson, 183). From this Luther insisted on the physical presence and physical eating of Christ: “On this we take our stand, and we believe and teach that in the Supper we eat and take to ourselves Christ’s body truly and physically” (Robinson, 183).

Luther did not deny a spiritual partaking of Christ or its necessity in order to partake of Christ. Rather, he taught that both were necessary. This arose out of his insistence that the believer needs the flesh of Christ for salvation.

His flesh is…a food of an entirely different kind from perishable food. Perishable food is transformed into the body of the one who eats it; this food, however, transforms the one who eats it into what it is itself, and makes that person like itself, spiritual, alive, and eternal; as Christ says, “this is the bread from heaven, which gives life to the world” (Robinson, 240).

His insistence on the physical presence and physical eating of Christ precipitated conflict with the Swiss Reformers, notably Zwingli and Oecolampadius. The conflict was largely unfruitful between them, mainly because the Swiss did not address with any great skill the real issues that Luther raised: what is the correct meaning of the words of institution; how is Christ present; and how do believers eat the proper and natural body of Christ unto eternal life?

There were also serious problems with the Swiss theologians’ doctrine of the supper, which Luther characterized this way: “our opponents say that mere bread and wine are present, not the body and blood of the Lord” (Robinson, 180). For Luther, that theology came out of their misinterpretation of the words of institution:

They say, “the word ‘is’ must mean the same as the word, ‘signifies,’” as Zwingli writes; and the expression “my body” must mean the same as the expression “sign of my body,” as Oecolampadius writes (Robinson, 184).

What particularly incensed Luther were the repeated appeals by Zwingli and Oecolampadius to John 6:63 against his view: “Now their second chief argument is the saying of John 6:63, ‘flesh is of no avail,’ which Oecolampadius boasts of as his iron wall” (Robinson, 222).

Oecolampadius’ argument was simple: flesh in this text refers to Christ’s flesh, and since Christ said that flesh does not avail, we must be content with eating Him spiritually in the supper. That argument rankled Luther because it showed that, whenever they talked about spiritual eating, it did not include the flesh of Christ, and for Luther that was the fundamental point.

The controversy came to a head in 1529 at the Colloquy of Marburg, a meeting of the German and Swiss Reformers called to hammer out an agreement on the doctrine of the Lord’s supper. Luther’s argument for his doctrine at the colloquy was brutally simple, “God said, ‘This is my body.’ God is omnipotent. Consequently, the body is in the bread” (Sasse, 181). Luther laconically summed up his opposition to the other Reformers at Marburg: “I abide by my text” (Sasse, 191). He summarized their differences thus:

Your argument implies this idea: Since we have the spiritual eating, there is no need of a bodily eating. To this I reply: We do not deny the spiritual eating; on the contrary, we teach and believe it to be necessary. But from this it does not follow that the bodily eating is either useless or unnecessary…. We have the command “Take, eat; this is my body”…Christ gives himself to us… in the Sacrament as often as the body of Christ is eaten, because he himself commands us to do so. If he ordered me to eat dung, I would do it. Let not the servant inquire about the will of the Lord (Sasse, 191).

After a last-ditch effort to salvage the meeting, Luther himself suggested a formulation that all the Reformers could sign:

We confess that, by virtue of the words, “This is my body, this is my blood,” the body and blood are truly (wahrhaftiglich)—that is: substantively and essentially, not quantitatively or qualitatively or locally—present and distributed in the Lord’s Supper (Sasse, 213).

In this same document the Lutherans admitted the following:

Since we so far have held the opinion that our dear sirs and brethren, Oecolampadius, Zwingli, and their adherents, totally reject the Real Presence of this body and blood, but now in friendly colloquy have found it to be otherwise, we now declare and state that the arguments and reasons found in our books concerning the Sacrament are not directed against and do not apply to Oecolampadius, Zwingli, and their adherents, but against those who totally reject the presence of the body in the Supper (Sasse, 215).

That was a massive admission. Luther left out anything about physical eating and tipped his hand that his real issue was the presence of Christ and the truth of His words. In his writings Luther often beautifully expressed his real contribution to the doctrine of the Lord’s supper: Christ is really present. His flesh and blood are present. It is a real supper of Christ’s flesh and blood. In the supper believers really eat His flesh and blood unto eternal life.

This is the truth Rome denied by making the sacrament a meritorious work or the source of grace to perform meritorious works; Zwingli eviscerated by emptying the sacraments of Christ altogether; Oecolampadius badly muddled or totally missed; Bucer probably saw, but was too busy crying “peace, peace,” to develop; and that Calvin would hone to a razor’s edge. Luther, as usual, did battle where the truth was at stake. Luther erred by explaining Christ’s presence as physical.

Recognizing Luther’s insights and both avoiding and rightly criticizing his error, Calvin continued Luther’s work and advanced his doctrine in a way that those who slavishly followed Luther did not. Calvin subjected Luther’s teaching to a thorough critique. He had to contend with Luther. The result of that engagement with Luther was a great advance in the doctrine of the Lord’s supper.

With his customary clarity, Calvin came to the heart of the issue: that Christ is the bread of life to believers “none but the utterly irreligious deny…but there is no unanimity as to the mode of partaking of him” (McNeill, 4.17.5). Calvin rejected as emphatically as Luther the position of those who teach that Christ is not present: “unless a man means to call God a deceiver, he would never dare assert that an empty symbol is set forth by him” (McNeill, 4.17.10). Calvin concluded:

I freely accept whatever can be made to express the true and substantial partaking of the body and blood of the Lord…and so to express it that they may be understood not to receive it solely by imagination or understanding of the mind, but to enjoy the thing itself as nourishment to eternal life (McNeill, 4.17.19).

Here Calvin conceded Luther’s main point: the sacrament is a supper of Christ’s flesh and blood.

The tangled question remained about the manner of the believer’s partaking of Christ’s flesh and blood. Calvin sliced the Gordian knot by a single stroke:

Even though it seems unbelievable that Christ’s flesh, separated from us by such great distance, penetrates to us so that it becomes our food, let us remember how far the secret power of the Holy Spirit towers above all our senses (McNeill, 4.17.10).

Calvin summarized his doctrine this way: “We say Christ descends to us both by the outward symbol and by his Spirit, that he may truly quicken our souls by the substance of his flesh and of his blood” (McNeill, 4.17.24). The Spirit is the way Christ communicates His proper and natural body to us in the sacrament.

Calvin advanced the doctrine of the Lord’s supper not only by explaining the role of the Spirit, but also in his understanding of the believers’ partaking by faith. Everyone agreed that faith is the instrument for spiritually eating Christ: “We admit indeed, meanwhile, that there is no other eating than that of faith.” But Calvin carefully distinguished his position from the others’:

Here is the difference between my words and theirs: for them to eat is only to believe; I say that we eat Christ’s flesh in believing, because it is made ours by faith, and that this eating is the result and effect of faith; or if you want it said more clearly, for them eating is faith: for me it seems rather to follow from faith.

Calvin recognized that this is “no slight” difference. By distinguishing between faith and the eating of Christ Calvin taught that by faith the soul becomes partaker of Christ “truly and deeply…that it may be quickened to spiritual life by his power” (McNeill, 4.17.5).

In turn, Calvin explained why this real spiritual eating of the real flesh and blood of Christ is the only eating of him:

Paul, in the eighth chapter of Romans, states that Christ dwells in us only through his Spirit. Yet he does not take away that communion of his flesh and blood, which we are now discussing, but teaches that the Spirit alone causes us to possess Christ completely and have him dwelling in us (McNeill, 4.17.12).

Because of this, the physical eating of Christ’s flesh is unnecessary, impossible, and implies serious false doctrine. Calvin pointed out that it denied Christ’s real body and the ascension, assaulted the glory of God and Christ, and introduced general, ineffectual grace.

Martin Luther erred seriously in his doctrine of the Lord’s supper; yet his dogged and oftentimes violent defense of certain crucial points and his insistence that the matter be settled, drove the controversy toward a solution. It is measure of the other Reformers’ towering respect for Martin Luther as the instrument of God to deliver them from the Roman lie that they endured—not without comment, complaint, and sometimes disgust—the personal abuse that Luther often heaped on them in order to deal with what he said about the Lord’s supper and to resolve the issues he raised.

In his doctrine of the Lord’s supper, Calvin was truly a disciple of Luther. Calvin did justice to all of Luther’s concerns. He corrected Luther’s errors. He advanced his insights. In the process, he explained the doctrine of the Lord’s supper in a way that did justice to the words of Christ, to the glory of God and the salvation of sinners by sovereign grace. Calvin’s gift to us from Luther is the Reformed doctrine of the Lord’s Supper found in the Reformed creeds. Reformed believers owe a debt of gratitude to both men, and to God for them.

1 The works cited in the article are Martin Luther, The Annotated Luther, Church and Sacraments, vol. 3, ed., Paul W. Robinson (Minneapolis: Fortress Press, 2016); Hermann Sasse, This Is My Body (Adelaide: Lutheran Publishing House, 1977); John Calvin, Institutes of the Christian Religion, ed., John T. McNeill (Philadelphia: The Westminster Press, 1960).