As was mentioned in the previous post, Lady Macbeth has made herself bold by drinking the same alcohol that she gave Duncan's chamberlains. After she claims that the alcohol has made her bold, Macbeth exits Duncan's chamber. Macbeth is visibly perturbed and tells his wife that he heard the servants say,
"Glamis hath murdered sleep, and therefore Cawdor shall sleep no more. Macbeth shall sleep no more" (Shakespeare, 2.2.42-43).
Lady Macbeth reveals her bold nature by commanding her husband to stop being a coward. Despite the fact that Lady Macbeth is unable to murder King Duncan herself because he reminds her of her father, she takes matters into her own hands by returning the bloody daggers to Duncan's chamber. Lady Macbeth again reveals her bold character by telling her husband,
"Infirm of purpose! Give me the daggers. The sleeping and the dead are but as pictures. 'Tis the eye of childhood that fears a painted devil" (Shakespeare, 2.2.52-55).
In relation to Macbeth's earlier quote about God's justice bringing the poisoned chalice to their own lips, Lady Macbeth's bold actions eventually come back to haunt the couple. Together, Macbeth and his wife have successfully assassinated King Duncan. Throughout the remainder of the play, both characters are forced to deal with the negative consequences of their actions. Lady Macbeth becomes so consumed with guilt that she eventually loses her mind.