Macbeth says that he’ll need to kill the Prince of Cumberland’ as next in line. So Macbeth is thinking how is he going to be king if the prince is in my way and even though he is power hungry and wants to kill them he still feels this guiltiness and a sense of loyalty and feels ashamed of himself for thinking those thoughts. ‘Stars, hide your fires; let not light see my black and deep desires’ It suggests needs to hides his desires as they are showing too much.