In Macbeth Act I, scene 5, Lady Macbeth greets her husband and receives his news that Duncan is on his way to their castle.
Lady Macbeth uses a strong combination of figurative language to capture her emotional response to her husband's news.
Lady Macbeth uses personification in referring to "the raven himself is hoarse that croaks the fatal entrance of Duncan" (39-40). Besides giving the raven given human qualities, Lady Macbeth also ascribes to him a prophetic voice; this type of bird was often thought to be a harbinger of doom. She transfers her own feelings to the bird, such as her desire for Duncan's death.
She employs personification again later in her speech with the wish that her "keen knife see not the wound it makes" (51). Her thoughts are of murder. She gives human qualities to the murder weapon, but she is really speaking to herself in an attempt to stay her resolve to carry out the foul deed.
Lady Macbeth addresses her husband through the use of metaphor:
Your face, my Thane, is as a book where men
May read strange matters. (67-68)
As she greets her husband, she observes his expression, and compares the open honesty in his face to reading an open book. Macbeth struggles to conceal his feelings. Lady Macbeth feels she must correct this, especially with Duncan's impending arrival. She suggests, using simile that Macbeth "look like th'innocent flower, but be the serpent under't" (64-65). Her comparison suggests that Macbeth conceal his true purpose, like the serpent (Biblical allusion), and have all the charm of the flower to his guest.
lm may be presented as a merciless character, however this changes as the play progresses and while the murder of duncan is being planned she claims to say she couldn't kill Duncan herself as he reminded her of her father, this may indicate that she isn't as merciless as she appears