In Shakespeare's Julius Caesar, Act 5, scene 3, Titinius uses a metaphor to lament Cassius' death; could you please explain this metaphor?
In Act Five, scene three, of Shakespeare's Julius Caesar, Titinius discovers Cassius who has had his servant kill him, believing all was lost in the battle with Antony and Octavius.
When Titinius seems Cassius, he begins to mourn the loss of his friend. His lament compares the setting sun with the ending of the life of Cassius. As the red rays of the setting sun sink past the horizon to disappear into the night, so too has Cassius—like the sun—sunk his red blood into the earth, and he has passed into the night like the sun. Shakespeare extends the comparison stating that Cassius is the sun of Rome, and it has set. As a day is over when the sun sets, the days of Cassius and his friends and army are over as well. There is no light to lead or warm them, only "clouds, dews, and danger."
O setting sun,
As in thy red rays thou dost sink to night, (65)
So in his red blood Cassius' day is set,
The sun of Rome is set! Our day is gone;
Clouds, dews, and dangers come; our deeds are done!
Titinius is lamenting the death of Cassius and all he stood for, even the hopes his army had, and that with Cassius' passing, it foreshadows the defeat of the conspirators' army—or this is how Titinius sees it before he, too, takes his own life out of his love for his dead friend.