ἁγνόστομος
From LSJ
ὃν οὐ τύπτει λόγος οὐδὲ ῥάβδος → if words don't get through, neither a beating will | if the carrot doesn't work, the stick will not work either | whom words do not strike, neither does the rod
English (LSJ)
ον,
A with pure mouth, Tz.H.6.33.
German (Pape)
[Seite 18] mit heiligem, reinem Munde, Tzetz.