A Treatise on the Unity and Trinity of God by Israel of Kashkar (d. 872). Introduction, edition and word index

Sammanfattning: The present work is a contribution to the study of Christian Arabic literature. An apologetic treatise on the unity and trinity of God incorrectly attributed to Yahya ibn Adi (d. 974) is edited for the very first time and provided with a comprehensive word index. The edition is based on six manuscripts found in Egypt. Four of these manuscripts have so far not been known to scholarly research. The introduction to the edition falls into two chapters. The first chapter focuses on the question of authorship. As a first step, is compared with the authentic works of Yahya ibn Adi and the pros and cons of an attribution to him are investigated. The points of references are doctrinal, lexicographic, and stylistic. Only by means of a hypothesis implying that the treatise is a very early work by Yahya can the traditional attribution be accepted. As a second step, the implications of a marginal note in the oldest manuscript are put to the test. According to this note, a certain al-Kaskari is the author of the treatise. In search for Christian Arabic authors related to Kashkar in Iraq, the two bishops of Kashkar both called Israel (d. 872 and 962) appear to be the most likely candidates for the authorship of the treatise. By relating the treatise to what we know of these two bishops and to what they have written, it becomes clear that the ninth-century Israel of Kashkar (d. 872) is the author. The conclusion is based on both external and internal arguments. Close parallels with regard to doctrine (unity and trinity), style and method of reasoning (the argument “a minore ad maiorem”), and terminology (“rasil”) are shown to exist between the treatise and Israel of Kashkar (d. 872). The second chapter contains a description of the manuscripts, the principles of edition and an outline of the treatise.