Being a new reader of ancient Greek philosophy, I find myself fascinated by how Plato puts into the mouths of his characters proverbs or quotes that come from either the Illiad or the Odyssey. It is hard not to have the impression that Homer's works were seen as authoritative in some way. What kind of repute did the blind poet's works enjoy in Antiquity, or at least in the era in which Plato lived?
Note: resubmitted due to a typo in the title.
Very high repute. Have you read Plato's Ion yet? The education of an aristocratic man involved memorisation of large swathes of poetry, and Homer was the most important poet to learn. In the 520s the tyrants of Athens had instituted regular quadrennial performances of Homer at the Panathenaia, and while previously lyric had been the most prestigious form of poetry, from that point on the popularity of Homer surged hugely and has never fully died away since.
Before that rise to glory, Homer seems to have been associated more with the Thebaid than with the epics we know today. The Trojan War had been a popular set of legends for a long time, but before 550 BCE, episodes from all throughout the war were popular in artistic representations. But after that point the events of the Iliad start to dominate, and account for around 50% of all artistic depictions. By the 460s or thereabouts the tragic poet Aeschylus was saying that his plays were slices from Homer's banquet.
Other poets were popular too: Plato cites Hesiod a lot as well. But Homer did hold a special place. One study even argues that some of Plato's dialogues are structured using the Odyssey as a model (Planinc, Plato through Homer, 2003). It's hard to judge to what extent this was primarily an Athenian thing, because nearly all our sources from that period are Athenian, and the one big exception, Herodotus, was an Athenophile.
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