The Lord’s Supper is a profound mystery, and yet it’s so simple that anyone who has taken a bite of food and a gulp of water can understand it. Some may be skeptical of this claim since this doctrine has caused some of the sharpest debates and divisions throughout church history. But, with Calvin, we should recognize that these difficulties are not inherent to the doctrine itself, but result from the influence of the church’s archenemy. In Calvin’s words,
Satan, to deprive the church of this inestimable treasure [that is, the Lord’s Supper], has long since spread clouds, and afterward, to obscure this light, has raised quarrels and conflicts to estrange the minds of simple folk from a taste for this sacred food… (IV.xvii.1).
For this reason, it becomes necessary for Calvin to spend another 80+ pages resolving “those difficulties with which Satan has tried to ensnare the world” and for us to join him in foiling the demonic traps in our own day. But as we go about this noble endeavor, we must never lose sight of the simple teaching of this profound mystery. In fact, our goal in resolving these difficulties should be to return to its simplicity. Winston Churchill once remarked, “A vocabulary of truth and simplicity will be of service throughout your life.” This wisdom holds true as we consider the doctrine of the Lord’s Supper, which services the nourishment of our spiritual life in Christ.
Calvin’s Simple Explanation
Calvin opens his discussion of the Lord’s Supper in his Institutes with a simple overview of its chief design:
God has received us, once for all, into his family, to hold us not only as servants but as sons. Thereafter, to fulfill the duties of a most excellent Father concerned for his offspring, he undertakes also to nourish us throughout the course of our life. And not content with this alone, he has willed, by giving his pledge, to assure us of this continuing liberality. To this end, therefore, he has, through the hand of his only-begotten Son, given to his church another sacrament, that is, a spiritual banquet, wherein Christ attests himself to be the life-giving bread, upon which our souls feed unto true and blessed immortality (IV.xvii.1).
The Simple Aim of the Lord’s Supper
The simplicity in which Calvin desired the Lord’s Supper to be understood and taught is reflected in article 35 of the Belgic Confession. In fact, as P. Y. De Jong notes, the confession is “an admirable and appropriate summary” of Calvin’s treatise. It begins with an echo of Calvin as it states the aim of the sacrament:
to nourish and support those whom [Christ] has already regenerated and incorporated into his family, which is his church.
The sacrament does not create faith and, therefore, is not a converting or adopting ordinance. Rather, it nourishes the already existing faith of the children of God and produces growth in grace (see Westminster Larger Catechism Q/A 168). It is the family of God sitting down for a nourishing meal. As my pastor said yesterday (in a sermon that inspired this post), our Father doesn’t neglect his children as to leave us anemic in faith; on the contrary, he willingly and readily supplies us with all that we need for a full and satisfied life in Christ.
A Simple Sign and the Twofold Life of the Believer
The confession next employs a helpful figure of speech to explain the simplicity of the Lord’s Supper:
Now those who are regenerated have in them a twofold life, the one corporal and temporal, which they have from the first birth and is common to all men; the other spiritual and heavenly, which is given them in their second birth, which is effected by the Word of the gospel, in the communion of the body of Christ; and this life is not common, but is peculiar to God’s elect. In like manner God has given us, for the support of the bodily and earthly life, earthly and common bread, which is subservient thereto and is common to all men, even as life itself. But for the support of the spiritual and heavenly life which believers have He has sent a living bread, which descended from heaven, namely Jesus Christ, who nourishes and strengthens the spiritual life of believers when they eat Him, that is to say, when they appropriate and receive Him by faith in the spirit.
The point is simple: just as we need nourishment for our physical life (our stomachs may grumble), so also we need nourishment for our spiritual life (our souls may pant). And our Father kindly provides for both. Our physical life is nourished by daily bread, and our spiritual life is nourished by living bread, Jesus Christ. The partaking of Christ, therefore, is not physical, but spiritual since we appropriate and receive him by faith. “Faith,” as De Jong comments, “is the organ of our spiritual participation in Christ, described so aptly [by the confession] as the hand and mouth of our soul.“ As truly as our physical life is nourished and strengthened by partaking of bread and wine with our mouths, so truly our spiritual life is nourished and strengthened by partaking of the true body and blood of Christ our only Savior in our souls by faith. A profound mystery, yet a simple truth with a simple sign.
 P. Y. De Jong, The Church’s Witness to the World, 379. This excellent commentary on the Belgic Confession can be found online here.
 De Jong, The Church’s Witness to the World, 380.