He believes no one can touch him now that he is King.
Macbeth now starts taking a turn for the worst. At this point when going to murder Duncan he envisions a dagger floating above his head. Macbeth wonders is what he is seeing is real, "dagger of the mind, a false creation / Proceeding from the heat-oppressed brain," (II.i.38-39). Killing Duncan was the first thing to start Macbeth's noticeable madness. Macbeth starts to lose his mind and speaks, .
"Will all great Neptune's ocean wash this blood.
Clean from my hand? No, this my hand will rather.
The multitudinous seas incarnadine,.
Making the green one red.".
(II, i, 142-145).
Macbeth sees the blood on his hands and fears it will never wash away, that there is enough blood to turn the whole sea red. Lady Macbeth then meets him and tries to calm him down telling him a little water will clear them of their deed.
However, Macbeth goes through many more situations to deepen his insanity. Macbeth feels Banquo and his son must now be killed in order to assure him as staying King of Scotland. This is again showing how Macbeth is in his pursuit of power. Macbeth now has again changed in character from a loyal, trustworthy man, to weak and dependent, and now to strong and determined. This is also where his confidence and sense of invincibility starts taking place. As Lady Macbeth told her husband earlier on in the play, "look like the innocent flower, / But be the serpent under't" (I.v.63-64), Macbeth now tells her to do almost the same. At this point, Macbeth digs himself deeper and deeper into his grave.
.
After hearing of Fleance's escape, and of Banquo being murdered, Macbeth goes into a state of madness where he sees the ghost of Banquo in his chair at the head of the dinner table at the feast. Macbeth does not act rational in this scene. Seeing this ghost does not do well on Macbeth's part, making him have an outburst adding to his madness as it is already.
