"Whose horrid image doth unfix my hair,.
And make my seated heart knock at my ribs,".
He decides within himself that he will leave the future take it's course and agrees with Banquo to talk of the occurrence at another time.
The next scene, scene 4, features Duncan, the King. He is talking to his son, Malcolm, while Lennox and his other son Donalbain are also present. They talk about the execution of the Thane of Cawdor and if it has been carried out yet. Macbeth arrives with Banquo, Ross and Angus, and this the first time in the play when Duncan actually thanks and praises the work Macbeth has done for his country, in person. Macbeth replies saying that he was simply doing his duty for his King and Country. Duncan says that he deserves much more and that Banquo is equally thankful for his good deeds.
Then Duncan announces that Malcolm shall be his heir. He names him Prince Of Cumberland, always successor to the King of Scotland. The audience and reader of this play would be shocked at this point, finding out that Duncan has made his son his successor, because they think that Macbeth would become King. Macbeth is also shocked at what has happened and says to himself that it is something that he must dodge, to get to the throne.
"The Prince of Cumberland - that is a step,.
On which I must fall down, or else o"erleap,.
For in my way it lies.".
"Stars hide your fires.
Let not light see my black and deep desires.".
This is one of the last things that Macbeth thinks before exiting the scene. It is clear that thoughts of murder are beginning show an attraction in Macbeth's mind and he knows that what he is thinking is wrong. But still he leaves the scene with a decision to act on what the future could hold. The scene ends with Duncan talking to Banquo and continuing his praises of Macbeth.
Lady Macbeth is introduced to the play in the next Scene, Scene 5. She is reading a letter from Macbeth, containing information about what the witches said and what Macbeth is currently feeling, unsure and frightened.