Behind every great man, there is a great woman, and behind Macbeth, of course, is Lady Macbeth.
Act 1 Scene 5 is the first glimpse the audience gets of the woman who knows Macbeth better than any other, and it almost seems as if she knows him better than he knows himself.
Lady Macbeth is very clear on what needs to happen, admitting that despite Macbeth's ambition, he is incapable of acting dishonorably to get what he wants.
The major theme of the text, the theme of appearance versus reality or confusion and opposites, re-emerges in this scene.
Lady Macbeth scorns Macbeth's good qualities because she knows they won't make him the king.
Lady Macbeth invokes evil spirits to help her achieve her goals, a powerful act in Shakespeare's audience.
Macbeth's response to his wife's instruction to kill Duncan is "We will speak further", indicating that he has already decided what he's going to do.
Macbeth's relationship with his wife shows who's in charge, with Lady Macbeth looking down on him slightly.
This dynamic has important consequences for Macbeth's character as the play progresses.