Even in the introduction to his section on preaching, Pope Francis gets specific with his advice. And there’s a lot of good advice here.
138. The homily cannot be a form of entertainment like those presented by the media, yet it does need to give life and meaning to the celebration. It is a distinctive genre, since it is preaching which is situated within the framework of a liturgical celebration; hence it should be brief and avoid taking on the semblance of a speech or a lecture.
The Holy Father’s diagnosis of long homilies:
A preacher may be able to hold the attention of his listeners for a whole hour, but in this case his words become more important than the celebration of faith. If the homily goes on too long, it will affect two characteristic elements of the liturgical celebration: its balance and its rhythm.
What is liturgical preaching, anyway?
When preaching takes place within the context of the liturgy, it is part of the offering made to the Father and a mediation of the grace which Christ pours out during the celebration. This context demands that preaching should guide the assembly, and the preacher, to a life-changing communion with Christ in the Eucharist. This means that the words of the preacher must be measured, so that the Lord, more than his minister, will be the center of attention.
Hoping not to get too far off the topic of the homily, it occurs to me that much of what is said here about preaching applies also to music. Music should avoid the appearance of a concert within the liturgy. Music must attend to and support the balance and rhythm of the Mass. Music also involves the notion of offering as well as a mediation of the grace of Christ. Does God, rather than the music ministry, remain the center of attention?