It is difficult to establish what exactly the dress of the presbytera looked like, especially because it is not clear to whom Gregory is referring here. Although the word presbytera usually denotes a woman which was a wife of a presbyter, there is some evidence that it was also employed to describe widows ([771]), which seems to fit better with the context of this letter.
Gary Macy saw this passage as a proof that presbyterae not only constituted one of the separate ordines, but also that they had their distinct garment. Macy argued, however, that these presbyterae were neither widows, nor merely wives of presbyters, but they had the right to celebrate Eucharist (which is extremely unlikely). Mary Schaefer entertains this possibility as well. See Macy: 76–77 and Schaefer 2013: 180.
This was not the first of Epiphanius' trips to Rome ([2328]). He seems to have enjoyed some special relationship with Gregory.
In an earlier letters mentioning Epiphanius, Gregory refers to him only as a presbyter ([2327] and [2328]). It seems that in the meantime he was promoted to archpresbyterate, or that he simply became the oldest among Cagliari's presbyters, thus earning the prefix "arch". He is mentioned as archpresbyter also in the letter 14.2 ([2330]).
Dey 2008 argues that xenodochium was a type of a monastic institution whose everyday obligation was the care for the sick. Thus, Martyn's translation of xenodochia as hostelries might be misleading.