I don’t know if there is a similar saying in English, but in Italy we say:
In English we say the same thing ("don't look a gift horse in the mouth"), but we probably shouldn't in any language: I think you'll find that the etymology of that phrase can be traced back to ancient Troy. Stay vigilant! Quote
A caval donato, non si guarda in bocca
Apparently the saying is from Saint Jerome of Stridone.
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Noli equi dentes inspicere donati
Back then, the horse was a vital productivity factor and something to care about for the owner's wealth.
Looking into a horse's mouth was usually done to see the state of the teeth as an indication of the health status and the age of the horse itself.
Probably the horse in the Odyssey and Eneyd has nothing to do with that, also because the "Trojan horse" probably is a translation error.
The horse was a ship in reality. This alternative translation makes that story more credible and sensible.
[quote ]According to Tiboni, the horse was not hippos, the Greek word for "horse," but hippos, a Phoenician term for a type of warship with a curving prow. [/quote]
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