Early in the play Macbeth, Macbeth has control over his actions, but due to the influence of other characters and his subsequent insanity, by the end of the play, Macbeth has no control over his fate Any subject. It goes over many contemplating thoughts, and like all Shakespeare plays, he tries to answer them.
Macbeth has left the banquet to ponder the idea of murdering King Duncan.
In fact, even before he commits his crimes the thought of them makes him miserable. He says that he met super natural forces upon the heath and recalled their predictions about his future.
Macbeth is aware of what he wants yet he is unwilling to share his thoughts with anyone other than his wife. It is stormy; there is thunder, lightning, rain and howling winds.