At noon, we cross a high, rocky plateau. An amoebalike flock of sparrows shapeshifts in the air above us. The birds funnel down to the ground, a small and dark tornado of wings. They transform into a man.

This man is so old and so thin that he wavers slightly, like the silvery underside of a poplar leaf in an imperceptible breeze. His hair is a patch of white sod. His skin is baked and weathered to the color of peat moss; his lower face shines with a patina of nickel-colored stubble. He smiles. Starbursts of wrinkles radiate from his dark brown eyes.

He seems happy to find us here. He motions us over to him with a wave of a calloused hand. He is wearing a worn green sweater, canvas trousers that hang like a sack from a length of hemp twine threaded through the belt loops. He is barefoot. His feet seem to be covered with the dust of many ages.

He slips off a battered yellow canvas backpack. The backpack seems empty. He reaches into it. "I have a gift for you," he says. "It isn't much. But maybe in return you will let me walk with you a while." Into each of our shirt pockets, he tucks one lire.

He walks, not with us, but a few yards behind. He's so quiet that every once in a while I turn around to see if he's still there. He's always there. He smiles and nods.

At first I think he's a hobo, but then I wonder if he's an old soldier. The backpack is from World War II, and the sweater is an old military issue, the kind made of lead-heavy olive wool with squared-off shoulders. It is frazzled across the chest with what look like frayed shrapnel holes, or bullet holes. It is blown out at the elbows; the grimy khaki shirt underneath is also blown out at the elbows; its threads dangle through the sweater's holes.

After while I realize my shirt pocket is getting heavier. I reach into it and pull out the lire. It has turned into a thick packet of US thousand-dollar bills. So has Edsel's. We whirl around and stare. The old man, he just smiles and nods.

Late in the afternoon, we stop at a spring to fill the canteens. Hours ago we stopped checking to see if our friend still walked behind us. He's there. We offer to share our rations with him, as he has nothing. He shakes his head.

"I must go now," he says. "I thank you for letting me walk with you. In return, I have one more gift."

From his backpack he brings out a black Bible about the size of his big workman's hand. The leather binding's edges are worn to brown suede. He opens the Bible gently on a large, flat rock, runs his hand once down over the page he has chosen. He tears out the page. He gives it to me.

As the page leaves his hand, his hand is no longer a hand. It is a sparrow that flutters away. Sparrows flock around us and spin off in all directions. Our friend is gone.

I look down to read the Bible page. The words fade from it so swiftly I can't catch them. And then the page, it is blank.