The article aims at casting new light on Mattia Preti’s well-known decoration of the vault of the conventual church of the Knight Hospitallers, now the Co-cathedral of Valletta. To a modern viewer the iconography of the decoration is all but simple. The iconographic scheme, it is argued, seeks to claim a nobler pedigree to the Order of Saint John by juxtaposing episodes from the life of the Baptist with portraits of individual knights, who by virtue of their deeds or destiny form clear analogies with the scriptures. The precursor of Christ is thus effectively established as precursor to the Order and the knights in turn become post-figurations of the Baptist. This theme of ideological post-figuration should be seen as an extension of the way in which the knights were taught to see the laws and virtues of the Order represented in visual forms.