It is Macbeth himself who conveys both power and control at this point, through his reaction (both private and public) to the sudden confirmation of one of the witches’ prophecies: that he is now become Thane of Cawdor. Although naturally startled, he manages to control his reaction publicly. At first he stalls for time, saying to Ross and Angus that ‘The Thane of Cawdor lives: why do you dress me in borrowed robes?’ Ross and Angus confirm what he might well already have guessed: that the present Thane is to be executed as a traitor and so his title will devolve upon Macbeth.
At this news of his promotion, Macbeth appears calm in front of the others, merely giving his thanks. However, along with his controlled public façade, he divulges his inner thoughts through a series of asides, and this reveals a very different aspect. We see that inside, he is excited and agitated by this turn of events, as he feverishly ponders the nature of the witches’ prophecies: ‘this supernatural soliciting’. Banquo has already cautioned him against these ‘instruments of darkness’ and we see now that the witches have indeed set him to thinking of evil things: namely, the murder of King Duncan which he sees as leading to the fulfillment of the witches’ final prophecy, that he will be king.
As yet, Macbeth’s musings only hint at this murder, it is not clearly spelt out at this stage. However, we see how such dark thoughts are already shaking him to the core: ‘why do I yield to that suggestion/whose horrid image doth unfix my hair/ and make my seated heart knock at my ribs/ against the use of nature?’ This description shows the power of evil, the evil that is within Macbeth himself, which is given impetus by the witches’ prophecies, as he begins seriously to contemplate committing regicide just to satisfy his own personal ambition. This power threatens to overwhelm him; his heart is thudding, his hair standing on end. He is thrown into turmoil by the prospect, yet it exerts an unholy fascination.
Macbeth becomes lost in these thoughts, so that Banquo remarks on how distracted, or ‘rapt’ he appears. Yet, once more, he is able to pull himself together, to retain his self-possession in front of his companions. There is the power of his inner darkness, which threatens to master him; but he remains calm on the outside. Thus, he controls the power of evil at this point. Macbeth successfully dissembles in this manner for much of the play, but the audience is made aware of his inner tumult.