The first two scenes of Macbeth reveal that Macbeth may be a stronger man of action than he is of thought.
Act I, Scene 1 is very brief: the three witches plan to meet Macbeth in an open field after the battle between the Scots and the Irish invaders.
In this scene there is little revealed about Macbeth other than that he is going to be involved with the supernatural realm of witches. Certainly, in the Elizabethan Age, there was a strong belief in supernatural phenomena and the suggestion that Macbeth may become enmeshed in the phantasmagoric realm of witchcraft makes Macbeth an intriguing character.
Act I, Scene 2 includes a description of Macbeth's battle with Macdonaldwald, the Irish traitor. A captain, wounded in the act of removing King Duncan's injured son Malcolm from the battlefield, describes the "brave Macbeth's" fight with this Macdonaldwald. Taking his sword, Macbeth "[D]isdaining fortune," stabs the Irish warrior in a brutal "bloody execution."
Like valor's minion carved out his passage...
Till he unseamed him from the nave to th' chops,
And fixed his head upon our battlements. (1.2.19-23)
Macbeth runs his sword from the man's navel up to his jaws, slaughtering him. With these brutal actions, Shakespeare introduces the blood trope which runs throughout the play and suggests the ruthless character of Macbeth and his murderous actions.
The following scene (Act I, Scene 3), certainly indicates the credibility which Macbeth gives the three sisters' prediction that he will become Thane of Cawdor and, then, king. But, it is also cause for concern on the part of Macbeth and the beginning of his mental disturbances:
This supernatural soliciting
Cannot be ill, cannot be good. (1.3.134-135)
Further, he is disturbed as reality and fantasy become equal, remarking, "nothing is but what is not" (1.3. 144). On the other hand, he is enticed by the idea of the witches' prophecies:
If chance will have me King, why, chance may crown me,
Without my stir. (1.3.146-147)