παραδειγματιστέον
From LSJ
εἰ δὲ τύχῃ τις ἔρδων, μελίφρον' αἰτίαν ῥοαῖσι Μοισᾶν ἐνέβαλε → if someone is successful in his deeds, he casts a cause for sweet thoughts into the streams of the Muses
English (LSJ)
A one must punish for example's sake, Id.35.2.10.