Virgil, Aeneid IV.174-175
Melphi speaks
Fama, malum qua non aliud velocius ullum;
mobilitate viget, viresque adquirit eundo,
The priest translates
«Rumour, an evil swifter than any other: she thrives on motion and gathers strength as she goes,»
And interprets
Be careful with rumours, both those running about you and those you might set running yourself. Right now a piece of news, a bit of gossip or a forwarded message can grow far faster than you imagine and reach, distorted, the very people who should not hear it. This line does not ask you to live in suspicion, but to be careful with words: what you say in confidence can swell along the way. If someone reports something to you, check before you react. If you have something important to say, in love or at work, say it yourself, first and plainly, before the rumour does.
The historical translations
È questa fama un mal, di cui null’altro
È più veloce; e com’ più va, più cresce,
E maggior forza acquista. È da principio
Rumor! What evil can surpass her speed?
In movement she grows mighty, and achieves
strength and dominion as she swifter flies.