This volume brings together a set of articles on the history of eastern Christianity and the Arabic traditions which, from the 8th century, gradually superseded those in Greek , Syriac and Coptic. In the first group of studies, Professor Troupeau looks at a number of particular aspects of Arabic Christianity - the literary history of the 10th-12th centuries (including a general survey of the topic, which opens the volume), its social history (monasteries and festivals), and the development of its own specific vocabulary. The following articles include editions and translations of scriptural texts and philosophical and theological treatises by Christian writers, Melkite, Jacobite, and Nestorian, and present works by some contemporary Muslim authors who were interested in Christianity. Dans ce volume, l'auteur a réuni des articles destinés à faire mieux connaître le christianisme oriental selon la tradition arabe qui, à partir du VIIIe siècle, se substitua progressivement aux traditions grecque, syriaque et copte. Un premier groupe d'articles concerne différents aspects du christianisme arabe: histoire littéraire du Xe au XII siècle, sociologie religieuse (couvents et fêtes), lexicographie (vocabulaire spécifique). Un second groupe comprend des éditions et des traductions de textes scripturaires et de traités philosophico-théologiques d'auteurs chrétiens des différentes confessions: melkites, jacobites et nestoriens, mais aussi d'auteurs musulmans s'intéressant au christianisme.