Following the most ancient customs and practices, the Church uses music and song in her liturgy. Music and song has always been a traditional part of the Eucharistic celebration.
In the Constitution on the Sacred Liturgy of Vatican II, there was a renewal of emphasis upon the singing by the people of God in community. “Religious singing by the people is to be skillfully fostered, so that in devotions and sacred exercises, as also during liturgical services, the voices of the faithful may ring out according to the norms and requirements of the rubrics” (SC 118).
Holy Scripture has bestowed praise upon sacred song, and the same may be said of the Fathers of the Church and of the Roman Pontiffs, who in recent times, led by St. Pius X, have explained more precisely the ministerial function rendered by sacred music in the service of the Lord.
The texts intended to be sung must always be in conformity with Catholic doctrine; indeed, they should be drawn chiefly from Holy Scripture and from liturgical sources.
The reform of the Liturgy brought about by Vatican II placed greater emphasis upon music as a communication medium, a participation in the liturgy by the people, and a renewal of the forms and applications.
All music of the Church should be worthy of the worship of God in whatever celebration this takes place. Such a effort must be carried on through a training in the priestly and diaconate candidates, liturgical appreciation, and catechesis of all Church members. (8:27)