ἐξορκοῦν

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

Source

Greek > English (Woodhouse Verbs Reversed)

(see also: ἐξορκόω, ἐξορκῶ) administer an oath to, administer oath to, tender an oath to

Lexicon Thucydideum

iusiurandum accipere, to administer an oath, 5.47.9,
Ibid. ter. in the same place a third time