One of the papers that did not really get delivered, because of technical problems, was by Allen Brent on pagan imagery in Christian art. He started by putting up a list of possible explanations. This he has kindly sent to me at my request, because I thought it was interesting all by itself. The explanation is that the art is:
1. Crypto Christian: an illegal society veiled its Christianity by using pagan forms that made it harmless in the eyes of hostile contemporaries (Wilpert).
2. Purely conventional: Sarcophagi and frescoes were simply the conventional products of a particular pagan workshop.
3. Represent iconography submitted to a process of expurgation that removes innocuous associations but leaves traces of paganism (Finney)
4. Pagan all along: their Christian appearance deceptive, like e.g. the Avercius Inscription or emanate from what is supposed to be a semi-Christian environment (e.g. Valentinus or Barbeliot Gnostics)
5. Products of a shared form of life (Wittgenstein) between Christians and Pagans where ability to disagree in opinion depended on agreement in formal, non-verbal iconographic categories (Brent).
The first option he considered simplistic, although I am not clear why. He did ask, tho, whether Roman officials were that interested in Christian burials. Those of us who remember the martyrdom of Polycarp, where the saint is denied burial, may query this.