The Oath in Late Antiquity and the Early Middle Ages

Religious Act, Social Bond, Holy Sacrament

Book cover: The Oath in Late Antiquity and the Early Middle Ages

Extent: 364 pages

Publisher: Wiley-VCH

Subjects: Medieval Studies, Religious Studies

Series: Cultural Encounters in Late Antiquity and the Middle Ages

Language: English

Hardback (Published)

(September 2026)

ISBN: 9782503621005

6.14 x 9.21 inches

Price: $138.00

Focusing on the uses of oaths in Christian contexts between the first and eleventh centuries, and on theologians’ reflections on swearing of oaths, the contributions to this volume take a closer look into the inner fabric of late antique and early medieval societies and their religiously-shaped conceptions of political loyalty and social cohesion.


In societies both past and present, oaths appear to be an almost universal phenomenon and an indispensable tool for creating social relations and obligations. In Christianity, however, their use is characterized by a fundamental tension: in the Sermon on the Mount, its founder explicitly forbade the swearing of oaths. Despite Jesus’ prohibition, the period between the fourth and the eleventh centuries witnessed an enormous spread and diversification in the use of oaths. This process generated a great deal of reflection and debates on the swearing of oaths, on their legitimacy, significance, and meaning, and also on their limits.

This volume provides a history of the oath in the West, from classical Rome to the Carolingian era. The contributions deal with the Biblical foundations of and Patristic attitudes towards oath-swearing, before moving to Late Antiquity, when Christianity came to dominate the discourse on the topic. The volume then focuses on the ninth century, when theologians began to regard the oath as a holy sacrament, discussed its relation to other sacraments, and reflected on oath-bound political loyalty — a topic that played a major role in the Investiture Controversy.

In surveying the use and theory of oaths in Christian contexts between the first and eleventh centuries, this volume offers a new perspective on the inner fabric of late antique and early medieval societies and their religiously-shaped conceptions of political loyalty and social cohesion.