This letter was addressed to Bishops Martyrius and Justus. They have been identified as the bishops of, respectively, Terracina in southern Lazio, and Acerenza in Basilicata or Larino in Molise. (Neil-Allen 2014: 193; PCBE Italie 1: Iustus 3, PCBE Italie 2: Martyrius 4, PCBE Italie 1: Amandianus 2). The distance between the localities is about 350 km (Terracina and Acerenza) or 200 km (Terracina and Larino). We do not know where the people bound by service to Amandianus lived, but logically it must have been in Southern Italy.
The "peculium" mentioned in the text is a personal property allowed to a slave or a non-emancipated son. Therefore, if a presbyter bound formerly by the obligation of service to someone was to lose his "perculium" to his master, it is as if he was to pay for his liberty.
For a similar problem see [2003].