of Publius Acilius Pisonianus
The evergete who financed the restoration of the speleum had the title of pater patratus ('confirmed', 'legitimate'), which is also attested, probably in a Mithraic context, at San Juan de Isla in Asturias (CIMRM 803). Originally, this title belonged to the head of the feudal priests, who was responsible for declaring war in accordance with the rules, but also for taking the oath, as in the pact between the Romans and the Albanians (Tite Live, I, 24). It is perhaps for the latter reason that this traditional Roman title was introduced into the Roman cults of Mithras, the god of oaths, thus marking the correspondence between the social values of this Milanese community and those of the Roman people. The generous donor acts – and finances – as a patron recognised by the group he leads.
This high stele by a certain Acilius Pisonianus bears an inscription commemorating the restoration of a Mithraeum in Mediolanum, today's Milan.
- Bricault; Roy (2021) Les cultes de Mithra dans l'Empire Romain