Scene one introduces the audience to one of the major themes of Macbeth: appearances can be deceiving.
"Fair is foul and foul is fair" (1.1.12).
In this scene, King Duncan hears that the thane of Cawdor has betrayed him; he also hears that Macbeth has bravely fought. Because of these two reasons, King Duncan declares that Macbeth will be the new thane of Cawdor.
"No more that thane of Cawdor shall deceive our bosom interest: go pronounce his present death, and with his former title greet Macbeth" (1.2.63-65).
"All hail, Macbeth! Hail to thee, thane of Glamis!" (1.3.49).
"All hail, Macbeth! Hail to thee, thane of Cawdor!" (1.3.50).
In scene three, the witches tell Macbeth his future.
"All hail, Macbeth, that shalt be king hereafter" (1.3.51).
SCENE 3 (Cont.)
"[King Duncan] bade me, from him, call thee thane of Cawdor" (1.3.107).
Ross and Angus tell Macbeth that he is now the thane of Cawdor.
SCENE 3 (Cont.)
Banquo believes that sources of evil (such as the witches) often tell the truth in order to lead to one's destruction. This belief foreshadows future events in the play.
"And oftentimes, to win us to our harm, the instruments of darkness tell us truths, win us with honest trifles, to betray 's in deep consequence" (1.3.125-126).
King Duncan suggests that they all go to Inverness, Macbeth's castle. Meanwhile, Macbeth realizes that he will have to take action to become king. Macbeth also realizes that his deepest desire is to become king. However, he does not want anybody to know this.
"Stars, hide your fires; let not light see my black and deep desires" (1.4.52-53).