Eucharistic preaching has to do with preparing the heart to commune with God. It must challenge the listeners to open themselves up to God while at the same time inspiring them with the true Gospel that clearly shows that God the Father invites us into His presence through His Son for healing, deliverance, forgiveness, strength, and joy.
The first eucharistic sermon was delivered by Jesus to His fellow travelers on the road to Emmaus. He opened up the scriptures to them which enabled them to recognize Him and understand His ministry. His sermon was not complete until He shared His body and blood with them through the elements of the Communion or Eucharist.
And it came to pass, as he sat at meat with them, he took bread, and blessed it, and brake, and gave to them.
And their eyes were opened, and they knew him; and he vanished out of their sight. And they said one to another, Did not our heart burn within us, while he talked with us by the way, and while he opened to us the scriptures? (Luke 24:30-32)
As a minister of the Gospel we must preach the Word. We must allow the scriptures to do their work. Our topical sermon is not going to get the job done. In order for our preaching to be effective we must allow the appointed readings to penetrate us as we prepare for the sermon. We must preach for metanoia or spiritual transformation, but first we must experience it ourselves. We must preach fresh manna.
Our sermon should prepare the entire congregation for an altar call and that altar call is the Holy Eucharist. The whole Eucharistic liturgy has been designed to prepare communicants to receive communion with Christ Jesus. This is done by allowing them to reflect upon the meaning of the scriptural readings not only in the context of biblical times but also within their own lives today.
The Apostle Paul said that we must examine ourselves before taking Communion. The “sermon” time allows for such examination. It must be followed by a time of prayer to give each listener the opportunity for personal reflection and, when appropriate, repentance. (A general prayer of confession should be built into the liturgy as a matter of practice. All have fallen short of the glory of God in some way.) Conviction of sin followed by prayer and confession leads to forgiveness and empowerment through the Eucharist. (See Eucharistic Theology and The Altar Call.)
Preaching the Lectionary 
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