What was the purpose of altering the text of the Lord's prayer?
This Hemingway story, more than any of his others, expresses the theme of "nada" or nothingness. The philosophy of "nada" as he develops it in numerous works is the idea that beyond human lives lies only a great nothingness--no God and no moral order in the universe. A "dark" void. The "light" motif represents man's attempts to find a way to endure the personal loneliness this philosophy evokes. Hemingway's characters frequently fear the dark, from Frederick Henry in A Farewell to Arms to the older waiter in this story. They cannot sleep in the dark.
In writing his ironic parody of The Lord's Prayer , followed immediately by the opening words of the Hail Mary, Hemingway replaces the comfort of traditional religious faith with the disturbing concept of nothingness. The older waiter and the old man drinking on the patio feel the loneliness and isolation of "nada," while the younger waiter is far too young to understand. It is the old man and the older waiter who need a clean, well-lighted place.