That was the “first act” of the Mass, the section when the priest offered up to God the wine and the small unleavened wafers called hosts. In the second act of the drama, the consecration, he transformed these banal elements, saying his magic words in Latin, holding the host up for all to see; it was the custom in Holy Name to hide one’s eyes and bow the head, refusing to look directly at the offered host because that little wafer had become God.
