"Yet do I fear thy nature; it is too full o' the milk of human kindness" was said by which character of William Shakespeare?

In "Macbeth" ( Act I, Scene V), the line "Yet do I fear thy nature; It is too full o' the milk of human kindness." is said by Lady Macbeth. This line in modern English means "I’m worried about your nature: It’s too gentle and kind".

Lady Macbeth is initially moving the cause regarding the death of King Duncan. She is concerned that Macbeth is not daring or treacherous enough, despite his ambition, to ensure that the witches' prophecy and end the life of the king.

In the beginning of the play, Shakespeare presents Lady Macbeth as a powerful lady who doesn't want to be trapped by what is expected within the existing society. In Shakespearean times, there were certain expectations about men and women. Men were seen as having strength, aggression, and rationality. Women, on the other hand, were associated with beauty, tender thoughts, and sensitivity. Lady Macbeth in this instance has strength, aggression, and can act with expediency. She has rid herself of a female persona; she is now powerful enough to commit an evil act (murder). By working with his wife, Macbeth overcomes any reluctance or doubt.

Following the murder of King Duncan, however, Lady Macbeth's role in the plot diminishes. She becomes an inactive spectator to Macbeth's plotting. She is a nervous hostess at the banquet dominated by her husband's hallucinations.