In his work Dr Walters starts from the premise that the traditional methods used in the study of art history distort our appreciation of Byzantine art. Development can be traced more plausibly, he argues, in terms of the function of the artefacts and the message they were designed to communicate. As well as seeking out the iconographical sources of medieval images, in antique and early Christian art, he is therefore concerned to establish parallels in medieval ceremony and literary sources in order to explain their meaning. The first articles here examine the iconography of local bishops and Dionysius the Areopagite, then concentrate on the imperial and official themes of the promulgation of authority, coronation and marriage. The next section deals with christological and hagiographical themes in the development of Psalter illustration, looking at the possible impact of the Iconoclast era and the changes that can be detected in how the psalms were seen and used.