The next point will probably sound the most foreign to contemporary evangelicals, sounding almost Roman Catholic. But the early reformers insisted that the bread and wine were signs of something present, not something absent - Christ was really spiritually present in the sacraments.
4. The Real Spiritual Presence of Christ. All of the words in that phrase are important. Christ is really present, if by real we mean 'true' or 'truly'. Calvin shied away from the word, though he did use it on occasion, because he was aware of the baggage it was loaded with. He denied that the bread became the body and the wine became the blood in a literal, physical way. The signs to not become the thing signified. Moreover, since Christ is in heaven he denied that he was locally present at the Table. But saying that Christ isn't locally present and that the signs don't become the thing signified does not mean that Christ is not truly present in an objective way. He is not only present in remembrance or sentiment, but truly present. The signs are not just bare symbols; there is a union ('sacramental union') between the sign and the thing signified.
How is Christ present when he remains bodily in heaven? Through the power of the Spirit. That is, I believe, what Calvin meant when he wrote about the spiritual presence of Christ. Saying that Christ is spiritually present can easily lead to misunderstanding. Calvin didn't mean that Christ is present only in the sense that the Spirit is present as his representative. The Spirit and Christ, while united in the Trinity, are separate persons and distinct from one another. Moreover, Calvin does not mean that Christ is present only in his divine nature. We communion with the person of Christ in the fullness of his divine nature and the fullness of his human nature. Calvin writes, "I am not satisfied with the view of those who while acknowledging that we have some kind of communion with Christ, only make us partakers of the Spirit, omitting all mention of flesh and blood."
So what does Calvin mean when he says Christ is spiritually present? He means he is made present through the power of the Spirit. While we are separated by a great distance from the person of Christ in his flesh and blood, the Spirit bridges that gap in a miraculous work. Calvin writes, "though it seems an incredible thing that the flesh of Christ, while at such a distance from us in respect of place, should be food to us, let us remember how far the secret virtue of the the Holy Spirit surpasses all our conceptions, and how foolish it is to wish to measure its immensity by our feeble capacity. Therefore what our mind does not comprehend let faith conceive - viz. that the Spirit truly unites things separated by space."
For Calvin to say that Christ is spiritually present doesn't mean he denies Christ is present in his flesh and in his blood, but that he is present in his flesh and blood through the Spirit. Thus, what Paul says in 1 Cor. 10:16, "The cup of blessing that we bless, is it not a participation [koinonia] in the blood of Christ? The bread that we break, is it not a participation [koinonia]in the body of Christ?" (ESV).
So, just as we really partake of the bread and cup, so we also really partake of Christ. The bread and the cup are taken by the mouth, Christ is taken by faith, being the "mouth and stomach of the soul." John Williamson Nevin explains,
“Here Christ communicates himself to his Church; not simply a right to the grace that resides in his person, or an interest by outward grant in the benefits of his life and death; but his person itself…Christ first, then his benefits"
“[The Reformed position] allows the presence of Christ's person in the sacrament, including even his flesh and blood, so far as the actual participation of the believer is concerned … A real presence, in opposition to the notion that Christ's flesh and blood are not made present to the communicant in any way. A spiritual real presence, in opposition to the idea that Christ's body is in the elements in a local or corporal manner. Not real simply, and not spiritual simply; but real, and yet spiritual at the same time. The body of Christ is in heaven, the believer on earth; but by the power of the Holy Ghost, nevertheless, the obstacle of such vast local distance is fully overcome, so that in the sacramental act, while the outward symbols are received in an outward way, the very body and blood of Christ are at the same time inwardly and supernaturally communicated to the worthy receiver, for the real nourishment of his new life. Not that the material particles of Christ's body are supposed to be carried over, by this supernatural process, into the believer’s person. The communion is spiritual, not material. It is a participation of the Saviour's life.”
5. This brings me to the last word I need to sum up the Reformed view as articulated by Calvin - 'miraculous'. Nevin points out that in the Calvinistic view, the communion of the believer with Christ in the Supper is beyond that experienced in common worship. Believer’s commune with Christ in the Supper in a unique way that is available in no other place. It is a mystery and indeed an actual miracle.Unfortunately, many modern approaches to the Meal empty it of its supernatural element, eliminating the mysterious and miraculous.
In case I haven't made this clear, Calvin's view is my own. In his teaching on the Supper, I believe he has done justice to Scripture and historic teaching of the church. It stretches our abilities to comprehend, and many have rejected his view for that reason. But that's no reason at all, much of what we affirm by faith stretches our ability to comprehend. We affirm, we don't always completely understand.
The Supper, in my view, is essential to the faith and life of the Christian. It is neglected only at great peril to both. It is to be observed in faith, with joy, thanksgiving and anticipation.