As well as acting as the messenger of the Gods, Hermes (Mercury to the Romans) was envisaged in the ancient world as the god of boundaries. Perhaps because of this, he is also sometimes represented as the guide who accompanies the souls of the dead to the underworld. Perhaps the most famous example is in the final book of the Odyssey, when he performs this function for the souls of Penelope’s suitors when Odysseus has killed them on his return to his home on the island of Ithaca.
Horace refers to this attribute of Mercury in an ode mourning the death of an upright and respected Roman named Quintilius. The academic evidence on precisely who Quintilius may have been is inconclusive, but Horace makes it clear that he was a dear friend of the poet Virgil.
Hear Horace’s Latin and follow in English here.