J.S.Bach
Wachet auf, ruft uns die Stimme (BWV 140)
It was quite compelling to learn in early September that this Cantata, based on a hymn familiar to many converts from Protestantism, has also particularly touched the Holy Father. (For those who wondered the origin of the title of this post, by the way, it can be found in the second Aria of the Cantata, at 20:15.)
