Conflict in Macbeth
Macbeth's soliloquy gives us an excellent characterization of Banquo and the reasons Macbeth has to fear him. We learn that Macbeth is not content with the crown while Banquo lives, and how Macbeth's character has deteriorated with power and fear. Recall how earlier in the play Macbeth hesitated and faltered over committing Duncan's murder. Now, despite their old friendship, nothing holds him back from plotting against Banquo.
Despite the depravity that Malcolm claims to have, Macduff continues to try and persuade him that the throne rightfully belongs to Malcolm and that the country is better off with him on the throne instead of Macbeth. Notice how Shakespeare maintains conflict throughout this scene to keep the dialogue engaging: first, Malcolm questioned Macduff's loyalty, and now Macduff encourages Malcolm to take what is rightfully his.