Still it cried “Sleep no more!” to all the house:
“Glamis hath murder’d sleep, and there Cawdor
Shall sleep no more, Macbeth shall sleep no more.”
– William Shakespeare
Macbeth, Act 2, Scene 2. Macbeth believes that he has reaped divine punishment by not being able to sleep again, because he has murdered the innocent King Duncan in his sleep. He hears an imaginary voice crying to all the house that Macbeth has murdered sleep so he will sleep no more. This is a sign of his guilt and inner turmoil, as he begins to fall apart mentally.