Foil between Macbeth and Banque

From a situational point of view Macbeth is predicted to become king while Banquo's sons are to be kings. In terms of personality, Macbeth has blind ambition to be king. He pretty much embarks on a murderous rampage to become king and secure his throne. On the other hand, Banquo is more introspective. He is happy with his sons becoming king and does not try to force his fate. While Macbeth trusts the witches, Banquo warns against them.