Halitgar (Halitgarius, Halitcharius, Halitgaire, Aligerio) was a ninth-century bishop of Cambrai (in office 817–831). He is known also as an apostle to the Danes, and the writer of a widely known penitential.
In 822 he travelled to Denmark as a missionary with Ebbo of Rheims and Willeric of Bremen, though not to great immediate effect. In 823 he was dedicating the church and relics of St Ursmer at Lobbes. In 825, with Amalarius of Metz, he carried the conclusions of a Paris synod on iconoclasm to Louis the Pious. He went as ambassador to Byzantium in 828.
De Paenitentia 
His De Paenitentia laid down qualities Christians should aspire to in their lives. He discussed a distinction between killing in warfare (a sin), and in self-defense in battle. Heavy penances for homosexual acts were imposed on older men. The work is also a source for information about surviving pagan practices.
It was written in five volumes, at Ebbo's request. Ebbo's intention was to have a normative penitential; Halitgar set aside tariffs of penances for exhortations. This work and the two attributed to Hrabanus Maurus were considered to supersede those written before, and were very influential, particularly in pre-Norman England. At this point, "the books used by confessors began to consist more and more of instructions in the style of the later moral theology".
His sources have been much debated:
- material from Gregory the Great, Prosper of Aquitaine, the Collectio Acheriana
- the Canons of Elvira and other old collections
- Julianus Pomerius
- a source common to Halitgar, the Collectio quadripartita, and the penitential writings of Hrabanus Maurus.
- Die altenglische Version des Halitgar'schen Bussbuches : (sog. Poenitentiale pseudo-Ecgberti), Darmstadt, Wissenschaftliche Buchgesellschaft, 1964
- Raymund Kottje (1980), Die Bussbucher Halitgars von Cambrai und des Hrabanus Maurus: Ihre Uberlieferung und ihre Quellen
- Carole M. Cusack, Conversion among the Germanic Peoples (1998), p. 135.
- http://users.skynet.be/bk342309/Lobbes/page7.html, in French.
- Rosamund McKitterick, The Frankish Kingdoms under the Carolingians (1983), p. 133.
- New Schaff-Herzog Encyclopedia of Religious Knowledge, Vol. V: Goar - Innocent | Christian Classics Ethereal Library
- Philippe Ariès, Paul Veyne, Georges Duby, A History of Private Life (English translation 1987), p. 536.
- Frederick H. Russell, The Just War in the Middle Ages (1975), p. 31.
- Janet L. Nelson, The Frankish World, 750-900 (1996), p. 78.
- Jody Madeira, Rebuilding the Closet: Bowers v. Hardwick, Lawrence v. Texas, and the Mismeasure of Homosexual Historiography(PDF), p. 10
- John T. McNeill, Folk-Paganism in the Penitentials, The Journal of Religion, Vol. 13, No. 4 (Oct., 1933), pp. 450-466.
- New Schaff-Herzog Encyclopedia of Religious Knowledge, Vol. II: Basilica - Chambers | Christian Classics Ethereal Library
- Henry Charles Lea, A History of Auricular Confession and Indulgences in the Latin Church I (1896), p. 105.
- Michael Lapidge, Anglo-Saxon England (2003), p. 227.
- Thomas Pollock Oakley, English Penitential Discipline and Anglo-Saxon Law in Their Joint Influence (2003), p. 31.
- Canon law - LoveToKnow 1911
- David Ganz, The Ideology of Sharing p. 26 in Property and Power in the Early Middle Ages (1995) edited by Wendy Davies, Paul Fouracre.
- Ghostly Recensions in Early Medieval Canon Law: The Problem of the Collectio Dacheriana and its Shades, The Legal History Review, Volume 68, Numbers 1-2, January, 2000