One important thing in the text that Macbeth says that tells you he will go even further in his change to become evil is: "I am in the blood/ I have intervened so far that, should I wade no more ,/ the return would be as tedious as the going./ I have strange things in mind that will be at hand,/ which must be enacted before they can be examined was to kill Macduff.Macduff suspected that Macbeth was the one who killed Duncan.Macbeth was also thinking of killing Macduff because macduff had gone to England to have Malcolm return and take over the rule of Scotland.Macbeth ended up deciding to send Macduff home someone who would kill his family. This would show Macduff that he needs to be careful about what he does, and would obviously scare Macduff. This would prove to be the final step Macbeth takes to become totally evil. In the end Macbeth has become so evil because he feels like he has basically sold his soul to Satan because of what he has done. This makes him think that he is already condemned to spend the hell of the afterlife. All the evil things and crimes he commits later have almost no moral meaning for him. He feels that at this point he should just get all the satisfaction he can from being king while he still is