This chapter re-examines the image of a canopied building supported by columns that often appears as the concluding page to the prefatory paratext to the gospels known as the Canon Tables, which was devised by Eusebius of Caesarea in the early fourth century. A catalogue of surviving examples of the so-called tholos image is provided, followed by an argument that the image is underdetermined and polyvalent, and that it operates together with the rest of the Canon Tables decorative scheme to invite an imaginative response from the viewer. The latter half of the chapter turns to two texts in Eusebius’ corpus to elucidate the way in which he used sacred architecture as a means of mapping the theological truths and ritual activities associated with such spaces. The same approach can be applied to the architectural decorative scheme adorning the Canon Tables, including its richly symbolic tholos, which can be seen as a potent symbol that can be activated through a biblically inspired ekphrasis and used as a ‘cognitive machine’ to theorise Christian knowledge and practice.

The primary subject of this chapter is the extensive ensemble of Second Style paintings found at two major ’Vesuvian’ villas: that of Fannius Synistor at Boscoreale and the Villa of Oplontis in Torre Annunziata. Together with our team of researchers, we were intensely involved in several international projects both in meticulously examining and analysing the organisation and decor of these villas, as well as creating highly detailed virtual reality 3D models of them. The chapter draws extensively upon the results of such research and work. We discuss further the striking relationship between the atrium paintings at Oplontis and the structural pattern of the scaenae frons, including that at the Large Theatre of Pompeii itself.