This study takes as its starting point the description of motet composition by Egidius de Murino, who says that the tenor should "concord with the matter" of the motet to be written. The repertory under consideration at this stage is the French tradition of the mid-fourteenth century, mostly transmitted in the complete-work manuscripts of Guillaume de Machaut (Paris, Bibliothèque Nationale, MSS fonds francais 1584, 1585, 1586, 9221 and 22545-22546, and New York, Wildenstein Galleries) and in the Ivrea codex (Ivrea, Biblioteca Capitolare, MS 115); this group is further limited to those motets for which a liturgical source has been identified for the tenor.
After an introductory chapter that traces modern scholarly interest in the tenor's role in the motet, chapter 2 examines the evidence for compositional manipulation of borrowed melodic material. The loss of liturgical propriety as a functional criterion allows the tenor to serve as more than a source of melodic and harmonic materials, and the possibility of alteration of a chant-based melody suggests the existence of other reasons for the use of a liturgical source. One of these, the use of liturgical function as a symbolic device, is explored in chapter 3, with special focus on a group of French-texted amatory motets that use tenors from Lent and Holy Week chants, a process that encourages an explicit comparison between the lover's sufferings and the passio of Christ. Chapter 4 examines another group of motets, also in French on the subject of love, that appear to name historical women by the liturgical context of their tenors; these motets are probably connected with the marriage or betrothal of the women named. Chapter 5 considers three new tenor sources discovered during the course of this study and suggests avenues for future work.