All over Rome there are traces of the same need for physical contact with the holy. In the church of Sant’Agostino there is a 16th-century statue of the Virgin of Child Birth, whose marble foot had to be replaced with silver because it was so worn from the touch of supplicants — usually anxious fathers expecting a difficult delivery. Now the metal foot is also worn smooth. Two small marble crosses were inserted into opposite piers of the Colosseum, which was thought to be a site of Christian martyrdom. An inscription below each cross states the number of years and days you would be spared Purgatory if you kissed it. Theoretically you could go back and forth between these crosses and kiss your way out of Purgatory. If this all sounds like a recipe for disease transmission, it probably is.

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