This rich and fascinating monograph is a unique study of a selection of sacred villancicos with texts about music. The generously scoped title invites readers into a very focused study with a breadth of implications toward a greater understanding of Spanish Catholics and their world around 1650. Villancicos were not the only music for worship heard in the vast and diverse early modern Ibero-American world, but they were key musical partners in the Catholic liturgy and public paraliturgical celebrations for major feasts like Christmas, Epiphany, and Corpus Christi. Their vernacular texts and exciting musical settings were part of their large public appeal. The title of Cashner's monograph acknowledges not only the omnipresence of the villancico genre but alludes to the villancico's significant power to contribute to scholarly research in early modern religious studies as well as music.

The book consists of two parts, with the first, “Listening for Faith,” introducing the repertoire of the author's study as well as his central analytical concepts and methodologies. Chapter 1, “Villancicos as Musical Theology,” leads the reader through close readings of the interplay of text and music in several of the monograph's featured villancicos, a subset of Cashner's survey of over eight hundred. The analysis begins with a discussion of villancicos that feature what the author terms “imitative references to music”—such as concrete cases where a reference to a bird in the text prompts musical trills or “twittering melismas” (18) in the music—and gradually moves toward discussion of how villancico composers represented the abstract, higher music of heaven and the angels. Cashner uses these examples to lead the reader gently toward an understanding of the Neoplatonic theological worldview, represented in part through the works of Luis de Granada (Introducción del símbolo de la fe, 1589) and Athanasius Kircher (Musurgia universalis, 1650). Engagement with Neoplatonic philosophy is a central thread throughout Cashner's book.

The principal theme of chapter 2, “Making Faith Appeal to Hearing,” contains a significant discussion of the terms listening and hearing, represented partly through detailed readings of villancico poetical and musical texts that highlight instances where communication is not possible or could fail altogether: for example, what about listeners who were not physically able to hear, or clerics who were not able to accommodate their teachings to a wide variety of hearers? Cashner argues in part that worshipers who listened to villancicos received what could be called “theological ear training” (56), engaging in a practice that would develop their listening skills with the purpose to increase their abilities to understand the theological ideas carried through the poetical and musical texts.

In part 2, “Listening for Unhearable Music,” the author focuses on three case studies of villancicos from Puebla (1657), Montserrat (1660s), and Zaragoza (1650–1700). Chapter 3, “Christ as Singer and Song (Puebla, 1657),” begins with an evocative and contextualizing description of the chapelmaster Juan Gutiérrez de Padilla leading his villancico, Voces, las de la capilla, in Puebla on Christmas Eve, 1657. This particular villancico is one of a family of settings of the same or closely related texts set by other villancico composers. Multiple musical settings of the same villancico text on the subject of music, especially, not only illuminate the networks between composers of villancicos but also display the variety of practices for representing the musical ideas of the texts, with composers thus demonstrating their mastery of “musical-theological tropes” (105).

Most of the villancicos discussed in detail in Cashner's book are included in their entirety in his critical edition, Villancicos About Music from Seventeenth-Century Spain and New Spain (2017), published as part of the Web Library of Seventeenth-Century Music (http://www.sscm-wlscm.org/). Revival of the villancicos Cashner has edited through recorded performance could be a valuable companion to Hearing Faith and would allow us to immerse ourselves completely in the text and music through active listening. But it would be the icing on the cake. On its own, Cashner's detailed and thorough presentation of the seventeenth-century villancico truly offers refreshing insight into how we can listen to and try to understand villancicos “through historic ears” (13).