Abstract zur Masterarbeit:With the 'Living Cross' in Thörl-Maglern (Carinthia) the painter Thomas of Villach transforms the comprehensive impact of the crucifixion death of Jesus Christ into a very detailed depiction, the analysis of which is the subject of this master thesis. The examination undertaken in this study ranges from the development of the 'image idea' ever since the 12th century to its literary foundation in early Christian texts, to the Patristic period and up to Thomas of Aquinas. The central focus of the fresco is the encounter of the defeated Synagoga and a victorious Ecclesia beneath the cross, which exemplifies allegorically the end of the Old Covenant and its substitution by the Church. Traces of the underlying theological anti-Judaism can be found in the liturgy of the Passion of Christ, and have contributed to the development of anti-Semitism ever since the crusades. The thesis investigates also the combination of both elements in medieval theatrical performances as well as in visual arts. Finally, the influence of these factors on Jewish life within the Christian society of the German Empire during the Middle Ages is discussed.