In addition to the English-language text of the document, Introduction: Lectionary for Mass, the late Ralph Keifer provides four chapters of commentary. His insightful and clear observations are still useful to any pastoral musician or priest. As he says, this document represents a significant turn in official statements of this kind. Here are his chapter headings:
The reform continues.
Words and music are central.
The Word proclaimed.
The liturgical year.
The author, for example, rightly points out that certain parts of the liturgy are identified in documents as "chants," that is, as elements that are meant to be sung. These would be litanies, responsorial Psalms, dialogues, and acclamations. Yet in many celebrations, he says, they are recited, not sung at all. Instead, people sing hymns. That's not the idea. As Keifer points out, Rome has been saying this sort of thing for a long time. We have yet to implement this norm, that certain parts of the Mass should be sung before all…