In the long post Vatican II season, one of the main problems had to do with the Mass Propers, the antiphons for introit, offertory and communion. De facto they disappeared from the common practice to remain as a sort of relic in the pages of the Roman Missal (introit and communion, but not offertory).
The perception was that this “new season, new spring, new beginning” was giving up the idea that the Propers of the Mass were still relevant, giving space to all kind of liturgical songs (“liturgical” in the best of situations). But this perception was and it is wrong.
It is true that the GIRM, the General Instruction for the Roman Missal gives the possibility to substitute the proper antiphon with another appropriate song, but this is a possibility of substitution, not a mandate to do so. The first choice should always be to use the proper antiphon for each liturgical feast and for each liturgical moment. This is what the GIRM asks.
To substitute the proper with another appropriate song is like going to a restaurant and having to eat something different from your favorite dish: “We are sorry, we have no pasta with salmon but we can give you instead pasta with meat sauce.” Yes, you don’t mind this second one but your first choice was another one, and eating too much meat is not healthy…
As for the situation we are concerned with, the antiphons are there, they never go out of stock! We should be more and more convinced that they are “healthier” than the possible alternative songs: they are from the Scriptures and are parts of the mosaic presented by the other readings of that specific day; they are specific for each liturgy, allowing us to go deeper in the understanding of the mystery celebrated that specific Sunday; they are presented following a pedagogy that go back for centuries.
I know that one of the main problems for some people concerning the singing of the propers is that the congregation is not supposed to be able to manage different antiphons every Sunday of the year but this is not correct: if this is the case they should not be considered capable of listening to different readings every Sunday, readings often based on arduous theological concepts or full of historical information. I think this is just one of the many excuses so that things can follow another direction, to reinforce the concept that making everything “easy” is good for the congregation.
One of my books is called “Il canto dei secoli”, The Song of the Centuries. Propers comprise this singing of centuries, because they were preserved during our history as a living witness of the faith of our fathers and mothers and as an incomparable tool to enhance the level of our liturgical prayer.