Violence is an important theme in Macbeth. Compare the murder of Duncan with the killing of Macbeth.
Violence is important in Macbeth, as in other Shakespeare plays. However, violence is difficult to portray on the stage. The murder of King Duncan occurs offstage, as does the discovery of his body by Macduff. Macbeth is also killed offstage. The stage directions say: They exit fighting. Later Macduff returns carrying Macbeth's head (which is, of course, a fake, a prop which is kept somewhere to be used whenever that play is enacted). Almost any violence on a stage looks faked, and there is always a danger of destroying the illusion the rest of the play has created. We have all seen plays in which one actor shoots another and the victim falls dead. The gun almost invariably sounds like a cap pistol and the actor who falls dead never does it convincingly. Shakespeare's forte was words, especially in iambic pentameter. The actual murder of Duncan was trivial compared to all the dialogue that went on before and after the event. The same is true with the killing of Macbeth. Typically, we imagine the violence from what is said about it.