67 Those in charge of the religious instruction of boys and girls should not neglect the proper use of these effective aids. Those in charge of Catholic youth should make prudent use of them in the highly important work entrusted to them. Thus there will be hope of happily attaining what everyone desires, namely the disappearance of worldly songs which because of the quality of their melodies or the frequently voluptuous and lascivious words that go with them are a danger to Christians, especially the young, and their replacement by songs that give chaste and pure pleasure, that foster and increase faith and piety.
Source: Musicae Sacrae (Vatican.va)