For preaching class in seminary, we were all required to write an essay on what we are trying to accomplish when we preach. This is what I wrote.
I am educating my congregation.
Because we affirm the Incarnation, the doctrine that God became flesh and lived among us as Jesus Christ in a specific culture and at a specific time and in a specific place, we are confessing that all truth from God is contextual. The Holy Spirit does not speak to us through a heavenly megaphone, but from within the context of the biblical writers and within the context of our everyday reality. Our context is ever changing. Thus I always have the task of interpreting our context relative to the biblical context; that is to say, my sermons always have an educational dimension—but an educational dimension without academic prerequisites.
I am bringing my congregation closer to personal faith.
All congregations live to some degree in denial, because the acknowledgement of hardship, distress, and adversity is not only unpleasant, it puts one at a social disadvantage. For this reason, the people in my congregation, having insight into their own souls, but not into the souls of others, tend to bear their own suffering in silence and solitude. If my sermon were to stop at the educational task, they would all be trivia experts who despair for their lives. I must not leave them there!
To proclaim Jesus as the Answer, I have to demonstrate that I understand the Question, and I have to demonstrate that the Solution fits the Problem. I have to read the Ecclesiastes in their souls before I can apply the gospels to their hearts.
My sermons cannot deny the demons of their spiritual pain; I must cast them out by name, filling the void they leave behind with the presence and love of Jesus Christ.
I am motivating my congregation to Christian discipleship.
I observe that very few people are bodily assumed into heaven upon praying, “Lord Jesus, come into my heart,” and that is because there is a reason for the interval between conversion and death that goes beyond fixing our destination as heaven.
If the church were an animal, Christian education would be its bones and faith would be its muscles, but even with flesh and bone the animal is not complete. An animal that does not move or interact with its environment is dead. Or as James says, faith without works is dead. So my sermon, having cast out the demons named in Ecclesiastes, having applied the balm of the gospels, must motivate my congregation to discipleship.
We confess Jesus Christ as Lord, but so did every demon in the New Testament. So how can you tell the difference between a Christian and a demon? It is only through our obedience, our service, our discipleship, and our stewardship, that we are better than the demons. Thus my sermon must move the congregation to action.
I am glorifying God.
God is glorified when His little ones struggle and prevail. My congregation is already struggling beneath their layers of respectable denial. When my sermon educates them, casts out their demons by name, and motivates them to Christian discipleship, only then does it equip them to prevail. When they prevail, God is glorified.
For this reason, I do not hold that the preacher is channeling God, to put it in New-Age talk. The Holy Spirit only speaks through me retroactively, after my sermon has educated my congregation, after my sermon has kindled their faith, after my sermon has motivated their discipleship, and only after that discipleship has born fruit in deeds of faith. Preaching is thus a sort of apocalyptic act, whose meaning is found only in its culmination.