From the embassy’s arrival in Iliad 9.180.
They went along the shore of the splashing sea
praying much to the earth-holding Earth-Shaker
to readily persuade the great heart of the son of Aeacus.
To the tents and ships of the Myrmidons they came,
and him they found delighting his heart with a clear-toned lyre
beautiful and skillfully embellished, and the bridge on it was made of silver,
then he took from the spoils when he had sacked the city of Etion:
With it he used to delight his spirit, and he sang the famous deeds of men.
Patroklos, alone with him, sat opposite keeping silence,
waiting until the son of Aeacus should leave off his singing….
τὼ δὲ βάτην παρὰ θῖνα πολυφλοίσβοιο θαλάσσης
πολλὰ μάλ᾽ εὐχομένω γαιηόχῳ ἐννοσιγαίῳ
ῥηϊδίως πεπιθεῖν μεγάλας φρένας Αἰακίδαο.
Μυρμιδόνων δ᾽ ἐπί τε κλισίας καὶ νῆας ἱκέσθην,
τὸν δ᾽ εὗρον φρένα τερπόμενον φόρμιγγι λιγείῃ
καλῇ δαιδαλέῃ, ἐπὶ δ᾽ ἀργύρεον ζυγὸν ἦεν,
τὴν ἄρετ᾽ ἐξ ἐνάρων πόλιν Ἠετίωνος ὀλέσσας:
τῇ ὅ γε θυμὸν ἔτερπεν, ἄειδε δ᾽ ἄρα κλέα ἀνδρῶν.
Πάτροκλος δέ οἱ οἶος ἐναντίος ἧστο σιωπῇ,
δέγμενος Αἰακίδην ὁπότε λήξειεν ἀείδων,
The scene is well-known for the depiction of Achilles playing the lyre himself for himself (the only amateur singer in Homer and only song not performed for a group) and for the thematic resonance of his singing κλέα ἀνδρῶν (deeds of men). It’s also been routinely observed that Achilles didn’t bring the lyre with him (which potentially suggests that the pleasure of song was felt to be incompatible with war, a social stricture which would explain why there are no singers in the Iliad otherwise), but I’ve never seen anyone poke at the potential character implications of the timeline and circumstances of its acquisition. But I’m lazy and do no more than point the way.