As I did stand my watch upon the hill,
I look’d toward Birnam, and anon, methought
The wood began to move.
– William Shakespeare
Macbeth, Act 5, Scene 5. Macbeth’s messenger reports that the Witches’ prophecy and warning of Birnam wood moving Dunsinane is coming true. In his arrogance Macbeth thought that the Witches’ prophecies made him invulnerable. Instead this passage foreshadows his doom.