Simile portrays Macbeth as the epitome of courage & chivalry.
Implies that Macbeth is an inferior servant of valour - he will blindly turn to violence & conflict, foreshadowing his vicious & brutal ambition.
"For brave Macbeth...which smoked with bloody execution" ↝ [a1s2]
Metaphor implies violence is a destructive force, just like fire.
He is 'brave' & highly skilled with his sword - both traits we typically associate with heroism. Shakespeare shows how violence & bloodshed are romanticised in the context of war. Because Macbeth is fighting for his country, his actions are righteous & honourable - ironic as when he behaves in the same ruthless way later, he's viewed as tyrannical & horrific.
Shakespeare could be criticising the culture of aggressive masculinity & honourable warfare.
"Stars, hid your fires...The eye wink at the hand" ↝ [a1s4]
Showcases how Macbeth wants to operate in darkness. This means he could avoid detection from others but more importantly, he doesn't have to witness his own corruption and villainy.
This quote exemplifies the contradictory, fragmented nature of Macbeth's character. The duality between light & dark is a symbol for the conflict between his morality & ambition.
"I have no spur...but only vaulting ambition witch o'erleaps itself" ↝ [a1s7]
Macbeth's hamartia is exemplified as he openly acknowledges that ambition drives him & influences him to act on his actions.
Suggests that ambition makes people think illogically & over-estimate themselves.
Shakespeare highlight Macbeth's hubris. This marks Macbeth's first act of heresy - excessive pride is condemned in the bible as it precedes destruction & leads to a fall. This foreshadows Macbeth's inevitable downfall.