Furiosius

1-2

Si quis eum servum, patinam qui tollere iussus
semesos pisces tepidumque ligurrierit ius,
in cruce suffigat, Labeone insanior inter
sanos dicatur. quanto hoc furiosius atque
maius peccatum est: paulum deliquit amicus,
quod nisi concedas, habeare insuavis: acerbus
odisti et fugis ut Rusonem debitor aeris,
qui nisi, cum tristes misero venere Kalendae,
mercedem aut nummos unde unde extricat, amaras
porrecto iugulo historias captivus ut audit.
(Horace, Serm. 1.3.80-89)

If a man were to nail his slave to a cross for eating
Left-over fish and cold sauce from the dish he’’d been told
To remove, sane men would call him madder than Labeo.
Well how much greater and more insane a fault is this:
When your friend has committed some slight offence,
That you’’d be thought ungracious not to have pardoned,
You hate him savagely, and shun him as Ruso is shunned
By his debtor. When the unhappy Kalends come, if he can’’t,
Poor wretch, rustle up principal or interest from somewhere,
He has to expose his throat, and listen to those sad Histories!
(tr. Tony Kline)

Octavius Ruso acerbus faenerator fuisse traditur, idem scriptor historiarum, ad quas audiendas significat solitum fuisse cogere debitores suos, quibus scilicet talia audire poena gravissima erat. hoc enim significat ‘porrecto iugulo’.
(Porphyrius, Comm. in Hor. Serm. 1.3.86)

Octavius Ruso is said to have been a rigid moneylender and also a writer of histories. Horace means that he used to force his debtors to listen to these histories – and for them this was no doubt a very cruel punishment. That is what he means by ‘to expose his throat’. (tr. David Bauwens)

Scurra

Nec semel inrisus triviis

And he who has once been fooled (tr. Henry Rushton Fairclough)

Hoc exemplo significat numquam postea crediturum quem esse etiam vera dicenti ei, qui falsis rebus omnia fidei argumenta consumpserit. hinc etiam proverbium natum est “qui semel scurra, numquam pater familias.”
(Porphyrius, Comm. in Hor. Epist. 1.17.58)

By this example [Horace] shows that one will never be believed in the future, even if he is telling the truth, if he has wasted his credibility in telling lies. Hence the proverb has arisen: “Once a scurra*, never a pater familias.”

* A scurra is a fashionable city idler, a man-about-town.

(tr. Christopher Francese, with his note)