πένθημι

From LSJ

ξένος ὢν ἀκολούθει τοῖς ἐπιχωρίοις νόμοις → as a foreigner, follow the laws of that country | when in Rome, do as the Romans do

Source

German (Pape)

[Seite 555] ist angenommen worden, um πενθήμεναι zu erkl. S. πενθέω).