A nurse on the pediatric ward, before listening to the little ones' chests would plug the stethoscope into their ears and let them listen to their own hearts. Their eyes would always light up with awe. But she never got a response to equal four year old David's. She placed the disk over his heart.

"Listen," she said, "Do you hear it? What do you suppose that is?" He drew his eyebrows together in a puzzled line and looked up – as if lost in the mystery of the strange tap-tap-tapping deep in his chest. Then his face broke out in a wondrous grin. "Is that Jesus knocking?" he asked.