I FIRST HEARD the Lord's Prayer in Mexico, during a family trip when I was 11 years old. I strayed from the Oaxaca market square, where my parents were bargaining over black pottery, and slipped into an old stone church, cool and dark. There were clusters of women in lace mantillas, and one or two solitary old men. Some were silent. Some whispered, some chanted in unison with the priest, "Padre nuestro que estas en los cielos: Santificado sea tu nombre." I never forgot the sound of ...