Why does Cassius hate Caesar?

Cassius hates Caesar because he is jealous of Caesar’s power and he believes that Caesar is a weak man and, therefore, undeserving of the power and admiration he has been given by the Roman citizens. To highlight his feelings, Cassius describes to Brutus how he once saved Caesar’s life when the two raced each other across the Tiber River. While he tells the story, he reveals his anger and resentment toward Caesar when he suggests that Caesar “[i]s now become a god, and Cassius is / A wretched creature [who] must bend his body” to him. During this conversation with Brutus, Cassius goes on to spitefully explain Caesar’s epileptic fits as another sign of the would-be emperor’s weakness. Caesar’s physical weakness, in contrast with his overreaching power, leads Cassius to judge Caesar as a danger to Rome and the Republic; he fears that Caesar will become emperor and strip the senators of their power, essentially enslaving them.