Juvenal, Satires 6.347-8
Perhaps the most famous quotation from Juvenal, most often applied today to the kind of corruption in high places which has been filling the UK news in recent weeks. But in its rather less high-minded context in Juvenal it concerns an eyebrow-raising way of dealing with your unfaithful wife…
audio quid veteres olim moneatis amici,
“pone seram, cohibe.” sed quis custodiet ipsos
custodes? cauta est et ab illis incipit uxor.
I listen to the advice you’ve long been giving me, old friends: ‘Put a lock on! Keep her confined!’ But who will guard the guards themselves? The wife has made provisions and starts with them!