After these few references to honour, the symbol of blood now changes to show a theme of treachery and treason. Lady Macbeth starts this off when she asks the spirits to "make thick my blood,". What she is saying by this, is that she wants to make herself insensitive and remorseless for the deeds which she is about to commit. Lady Macbeth knows that the evidence of blood is a treacherous symbol, and knows it will deflect the guilt from her and Macbeth to the servants when she says "smear the sleepy grooms with blood.", and "If he do bleed, I'll gild the faces of the grooms withal, for it must seem their guilt."
When Banquo states "and question this most bloody piece of work," and Ross says "is't known who did this more than bloody deed?", they are both inquiring as to who performed the treacherous acts upon Duncan. When Macbeth is speaking about Malcolm and Donalbain, he refers to them as "bloody cousins"
A final way, and perhaps the most vivid use of the symbol blood, is of the theme of guilt. First Macbeth hints at his guilt when he says "Will all great Neptune's ocean wash this blood clean from my hand?", meaning that he wondered if he would ever be able to forget the dastardly deed that he had committed. Then the ghost of Banquo, all gory, and bloody comes to haunt Macbeth at the banquet. The sight of apparitions represents his guilt for the murder of Banquo which he planned. Macbeth shows a bit of his guilt when he says "It is the bloody business which informs thus," he could not get the courage to say murder after he had killed Duncan, so he says this instead.
Lady Macbeth shows the most vivid example of guilt using the symbol of blood in the scene in which she walks in her sleep. She says "Out damned spot! Out I say! One: two: why then 'tis time to do't: hell is murky. Fie, my lord, fie, a soldier, and afeard? What need we fear who knows it when none can call out power to account? Yet who would have thought the old man to have had so much blood in him?". This speech represents the fact that she cannot wipe the blood stains of Duncan off of her hands. It is ironic, that she says this, because right after the murder, when Macbeth was feeling guilty, she said "A little water clears us of this deed." When the doctor of the castle finds out about this sleepwalking, he tells Macbeth "As she is troubled with thick-coming fantasies,". What this means, is that Lady Macbeth is having fantasies or dreams that deal with blood. Macbeth knows in his mind that she is having troubles with her guilt, but does not say anything about it.
Just before the ending of the play, Macbeth has Macduff at his mercy, and lets him go, because of his guilt. He shows that he is guilty, when he says "But get thee back, my soul is too much charg'd with blood of thine already.". Of which, Macduff replies, "I have no words, my voice is in my sword, thou bloodier villain than terms can give thee out."
After the death of Macbeth at the hands of Macduff, the symbolic theme of blood swings back to what it was at the beginning of the play. It is the symbol of honour to Malcolm this time. The death of Macbeth is honoured feat that Macduff is congratulated for.
So as we have seen meaning of the symbol of blood change from honour to treachery, and then to guilt, after this, it returns to the symbolic meaning of honour once again after the villain that changed the meaning from honour to tyranny is killed. Due to these many changes, it has been proved that the symbol of blood has many different meanings which can be attributed to it throughout the course of this play.
