Great marshal Atrides, lord of men Agamemnon –
if only you’d never begged the dauntless son of Peleus,
holding out to Achilles trove on trove of gifts!
He’s a proud man at the best of times, and now
you’ve only plunged him deeper in his pride.
I say have done with the man –
whether he sails for home or stays on here.
He’ll fight again – in his own good time – whenever
the courage in him flares and a god fires his blood.

– Homer

The Iliad, Book 9, lines 850-858. Diomedes tells Agamemnon that he has only offended Achilles’s pride even more by offering him a trove of gifts to return to the war. He advises Agamemnon to ignore Achilles, that he will fight again in his own good time.