The sermon or homily is not a lengthy dissertation. It is not a teaching on philosophy. It is not an impartation of factual statements about the faith. Rather, it should use an economy of words similar to a poem. Much can be expressed in poetry. The poet can express deep meaning without spelling out great detail. This, of course, requires the listener to do some of the work. Through careful listening the listener must be engaged and open to what the homilist might be saying.
The Gospel of John is very poetic. It has the simplest vocabulary of all the Gospels. Yet the Gospel of John is very deep with meaning. Each time it is read it is able to convey new levels of understanding. How does this happen? The Holy Spirit continues to breath new.
The homilist does not deliberately attempt to right a poetic homily. Rather. the homilist is open to the Holy Spirit, allowing the Spirit to have a major role in shaping and phrasing the text of the homily. A homily should come from God through much prayer and meditation on the chosen scripture. In this way, the sermon or homily becomes a particular word for a particular people at a particular time and place. Different listeners may hear different messages which might seem specific to each one of them. That is why we say that the sermon or homily is like a poem.