Adam Clarke on John 18:17

The damsel that kept the door - Caezarius, a writer quoted by Calmet, says this portress was named Ballila. It is worthy of remark that women, especially old women, were employed by the ancients as porters. In 2Sam 4:6, both the Septuagint and Vulgate make a woman porter to Ishbosheth. Aristophanes, in Vespis, v. 765, mentions them in the same office and calls them Σηκις, Sekis, which seems to signify a common maid-servant: - Ὁτι την θυραν ανεῳξεν ἡ Σηκις λαθρα.

And Euripides, Troad. brings in Hecuba, complaining that she, who was wont to sit upon a throne, is now reduced to the miserable necessity of becoming a porter, or a nurse, in order to get a morsel of bread. And Plautus, Curcul. Act. i. sc. 1, mentions an old woman who was keeper of the gate: -

Anus hic solet cubitare custos janitrix.

Why they, in preference to men, should be pitched upon for this office, I cannot conceive; but we find the usage was common in all ancient nations. See the notes on Mat 26:69.