Throughout the history of the Crusades, liturgical prayer, masses, and alms were all marshaled in the fight against Muslim armies. In Invisible Weapons, M. Cecilia Gaposchkin focuses on the ways in which Latin Christians communicated their ideas and aspirations for crusade to God through liturgy, how public worship was deployed, and how prayers and masses absorbed the ideals and priorities of crusading. Placing religious texts and practices within the larger narrative of crusading, Gaposchkin offers a new understanding of a crucial facet in the culture of holy war.