Cummian’s Letter De controversia paschali and the De ratione conputandi

Edited by
Maura Walsh and Dáibhí Ó Cróinín

Studies and Texts 86. 1988. x, 264 pp. ISBN 978–0–88844–086–0

A new edition of Cummian’s letter on the Paschal controversy, and a critical edition of a contemporary Irish computistical manual.

Cummian’s Letter on the Paschal controversy was first published in 1632 by Archbishop James Ussher from the sole surviving manuscript copy. The Letter is now re-edited for the first time since the seventeenth century. The significant advances made since Ussher’s time in the general area of Hiberno-Latin studies, and in the field of Insular computistics in particular, have made a new edition of the Letter a long-felt desideratum. Besides the critical edition, this volume contains a translation, historical introduction, and detailed technical commentary, to meet the more exacting requirements of modern scholarship.

Cummian’s Letter provides a unique insight into the procedures followed by the early Irish churches when faced with a major dispute, and it provides as well an invaluable index to the state of computistical and general patristic learning in Ireland in the early seventh century.

The text De ratione conputandi, first edited in this volume, is a computistical manual composed in Ireland probably in Cummian’s own time and possibly in his immediate circle. It incorporates most of the information which Cummian and his contemporaries drew upon in their studies of the Easter question, and marks a stage in the development of computistical science immediately prior to the Venerable Bede’s great works on time. Without it, much of what Cummian has to say would be unintelligible, and this critical edition with detailed commentary will allow the reader to appreciate better the technical aspects of Cummian’s Letter which form the essential core of that text.

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