If the joy of Christmas ever breaks through the frenzy of event-going and present-wrangling and (for me) end-of-semester grading, it happens through music. This year, for instance, I sat in my city’s gorgeous basilica and listened to a youth choir perform a haunting, dissonant arrangement of “O Come, O Come, Emmanuel.” The sound of the voices and organ in that space for a few transcendent moments nearly lifted me off the pew. No one can deny that the church’s writers and composers over the centuries have put their best efforts into music celebrating the Incarnation.