When we were in the novitiate, we noticed that when we served him Mass, after reading the Introït, Gradual, Offertory and Communion - in short, all the choral pieces - he would pause for a moment, unforeseen by the rubrics, and absorb himself in meditation. One day, one of us dared to ask him why he paused in this way, and he got this answer: "For these pieces of chant, the missal only gives the text, which is open to many interpretations. What I'm interested in is the Church's interpretation, and I believe it's very clearly expressed by the melody with which this text is clothed in the Gradual. So, let me stop and think about it for a moment. You see, Gregorian is the official commentary, authentically given by the Church itself, on liturgical texts.
Those who deliberately disregard the melody as an unnecessary luxury, and stick to the text alone, are depriving themselves of a great help. For it is the melody that defines the true meaning, scope and climate of the Church's prayer.
The Church recognizes Gregorian chant as the proper chant of the Roman liturgy. All other things being equal, Gregorian chant must take pride of place in liturgical actions. Other genres of sacred music, but especially polyphony, are by no means excluded from the celebration of divine offices, provided they are in keeping with the spirit of the liturgical action. [Sacrosanctum Concilium, n°116]
- Sacred music, as an integral part of the solemn liturgy, participates in its general end: the glory of God, the sanctification and edification of the faithful. It contributes to enhancing the dignity and splendor of ecclesiastical ceremonies; and just as its principal role is to coat with appropriate melodies the liturgical text proposed to the intelligence of the faithful, its proper end is to add greater effectiveness to the text itself, and, by this means, to more easily arouse the faithful to devotion and better dispose them to reap the fruits of graces that the celebration of the Holy Mysteries procures.
- Sacred music must therefore possess to the highest degree the qualities proper to the liturgy: holiness, excellence of form, from which its other character spontaneously springs:
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- Gregorian chant possesses these qualities to the highest degree; for this reason, it is the proper chant of the Roman Church, the only chant it has inherited from the ancient Fathers, the one that over the centuries it has guarded with jealous care in its liturgical books, that it presents directly as its own to the faithful, that it prescribes exclusively in certain parts of the liturgy, and whose integrity and purity recent studies have so happily restored. [Tra le sollecitudini]
For these reasons, Gregorian chant has always been considered the most perfect model of sacred music, for the following general rule can rightly be established: An ecclesiastical musical composition is all the more sacred and liturgical the closer it resembles Gregorian melody in allure, inspiration and taste, and all the less worthy of the Church the further it deviates from this supreme model.