[Jesus] said to him, "You shall love the Lord your God with all your heart, and with all your soul, and with all your mind." -Matthew 22:37
Bruno Walter was once rehearsing a choir for a performance of Bach's Saint Matthew Passion. He was trying to get the choir to sing the main chorale a certain way. (Think of the hymn "O Sacred Head, Now Wounded," and you'll have the music.) Walter kept rehearsing the choir, and they kept trying; but they weren't giving him the sound he wanted.
So he called a halt and said something like this: "Your singing is talented, but it's not right for this music. You need to sound more like a congregation. You've got to sing this chorale more simply and deeply." Walter told some of his boyhood memories of going to church in Germany and the way people sang there. Then he said to the choir: "Now sing this chorale as if you were back in my childhood church."
So they sang again. They sang with simple depth, with deep simplicity. Of course, they didn't sound exactly like a congregation. They probably couldn't have sounded like that if they had tried. They brought all their musical understanding to the singing of the chorale and thus sang it with an educated simplicity, with a second simplicity, with a simplicity that lay beyond complexity.
We all know this phenomenon. According to a famous story, the great Swiss theologian Karl Barth was once asked to sum up the thousands of pages of his dense theology in one sentence. He paused. Then he said, "Jesus loves me! this I know, for the Bible tells me so."
It's one thing for a child to recite these words and quite another for Barth to say them. It's one thing to fool around at a piano by plunking out the notes of "Twinkle, Twinkle, Little Star" with your index ...