Laura Davis contemplates what makes music sacred:
The Catholic Church makes its definition of sacred music pretty clear, stating in Musicam Sacram that music for the mass must “be holy, and therefore avoid everything that is secular.” It goes on to say that sacred music must also be “universal in this sense.” … I think it’s fair to say that the music has to be about God. The word sacred by definition must have to do with God or the gods, and most of the music of the contemporary worship movement fits this criterion. Perhaps then we should consider the purpose of sacred music: to function as part of the mass or service, most often as a part of worship. Worship derives from Old English weorthscipe ‘worthiness, acknowledgement of worth’. So if sacred music is intended to worship God, then such music must be of worth.
Kenan Malik suggests an alternative definition, one that operates “[n]ot so much as an expression of the divine, or as a set of rules and taboos, but, paradoxically perhaps, more [as] an exploration of what it means to be human”:
From the late medieval period on, ‘sacred’ art became increasingly humanized. The German critic Eric Auerbach called Dante, in the title of a famous study, a ‘poet of the secular world’. Dante’s Divine Comedy, despite its focus on the eternal and immutable features of heaven and hell, is at heart, Auerbach insisted, a very human exploration of this world. The human takes centre stage in The Divine Comedy, in way that had not happened previously in Christian thought. In this, Dante looks forward to the poets and artists of the Renaissance and beyond. Eventually the sense of transcendence in art came to be detached from religion entirely as in twentieth-century works such as Stravinky’s Rite of Spring or in Rothko’s paintings, in many of Barbara Hepworth’s figures or in Pablo Neruda’s love poems. It makes little sense to call such works of art ‘sacred’. There is, yet, a transcendent sensibility that links these to, say, works such as Bach’s Cantatas or Giotto’s frescoes or Dante’s Divine Comedy. To lose sense of that is to diminish both what is ‘sacred’ about sacred art and what is transcendent about much non-religious art.
(Video: performance of Bach’s cantata 184 “Erwünschtes Freudenlicht” (O welcome light of joy))