Doctor Luther, when commenting on the liturgy, came to the Words of Institution and drew our attention, not to the ceremony or the elements or the communicants, but to the Words of Christ. He bid the reader look at those plain, clear Words and focus on each one of them. “Everything depends,” he wrote, “upon the Words of the Sacrament. These are the Words of Christ. Truly we should set them in pure gold and precious stones, keeping nothing more diligently before the eyes of our heart, so that faith may be exercised.” (AE 53:79-80). And in the Large Catechism he writes, “With these words Jesus institutes the Sacrament, mandates its use and reception, consecrates the elements, informs the Christian of what he receives, strengthens the Christian’s faith and conscience, while providing sustenance for the Christian’s soul and body.” (LC V 23)
Why does the Pastor preach? Scripture explains that the role of preaching the Word of God is how saving faith is created: “How then will they call on Him in whom they have not believed? And how are they to believe in Him of whom they have never heard? And how are they to hear without someone preaching? And how are they to preach unless they are sent? As it is written, ‘How beautiful are the feet of those who preach the good news!’ … So faith comes from hearing, and hearing through the Word of Christ” (Romans 10:14-17). The Augsburg Confession, seeing this connection between the Preaching Office and saving faith, summarizes Scripture on the Office of the Holy Ministry in this way: “To obtain [saving, justifying] faith, God instituted the Office of Preaching, giving the Gospel and the Sacraments. Through these, as through means, He gives the Holy Spirit who produces faith, where and when He wills, in those who hear the Gospel. It teaches that we have a gracious God, not through our merit but through Christ’s merit, when we so believe” (AC V 1-3). The whole reason the Pastor preaches is so saving faith can be created, so we know that “we have a gracious God” who loves us and has saved us from our sin by the death and resurrection of Jesus Christ.