The boy draws lines and letters in the sand-filled pie tin. Then he says, louder than I expect, “I’m sorry, God!” as he shakes the pie tin, returning the sand to its smooth, undisturbed state. I offer him another pie tin filled with glitter, and he gleefully sticks both hands in and swirls them around. “Grace is like glitter!” he says. “No matter how hard we try, we can’t get rid of it!” And then, before I even realize what is...