The Holy Spirit is active in the sacrament of the Lord’s Supper. This word sacrament that we use comes from the Latin word sacramentum, which in its turn is the translation of the Greek word mysterion, or mystery.
In what way is this a mystery, and how does the power of the Holy Spirit come into it? The physical body of the Lord Jesus is in the heavenly places, at the right hand of God the Father. We do not believe that His body is locally present on this table—in other words you are not looking at Jesus, captured or contained by bread and wine. But the Scriptures plainly teach that we in the church are yet members of His flesh and of His bones. We partake of His body, and this partaking is a true verb. But how can we do this without Him being locally, physically present?
The Holy Spirit is the God of all miracles. He is the One who accomplished the work of Incarnation in the womb of Mary. He is the one who raised our Lord Jesus from the dead. He is the one who animates the church as the body of Christ. He is the one who escorts us into the heavenly places, so that we by faith can partake of the true humanity of Jesus Christ.
So we are what we eat. But take note here—we do not eat dead matter. By the power of the Holy Spirit, we are enabled to apprehend Christ by faith, and in the motions of eating and drinking, we are nourished and grown up into what we are eating. But we are eating resurrected, living and true humanity, and we do so in a mystery. This is why we are becoming human.
But the mystery, the sacrament, does not happen in the front of the church, where you have to crane your necks to see it. It does not happen on the Table. It happens as we take, eat, drink, taste, and swallow. The Holy Spirit does all this, and we do not have to worry about making it happen. He makes it happen, and He understands it. We do not need to understand it—we just have to taste it and look around with gratitude as we see the rest of the body tasting as well. And so this is what we do, discerning the body.