Discuss the role that blood plays in Macbeth, particularly immediately following Duncan’s murder and late in the play. What does it symbolize for Macbeth and his wife?
The most important use of blood - besides the "blood" Lady Macbeth is always trying to wash off - is in Macbeth's description of Duncan. Duncan looks silver but bleeds gold.
idea of who is fit to rule - an idea Macbeth seems partial to, as it drives him crazy - is inherent in the blood he sees. And I think you can see how blood nicely contrasts Macbeth and his wife. She's the lust for power, but he actually gets power.