To be, or not to be? That is the question whether 'tis nobler in the mind to suffer the slings and arrows of outrageous fortune, or to take arms against a sea of troubles, and, by opposing, end them?
Hamlet: Act III, Scene III
I'd better think about this more carefully. A villain kills my father, and I, my father's only son, send this same villian to heaven.
Hamlet: Act III, Scene IV
You low-life, nosy, busybody fool, goodbye. I thought you were somebody more important. You've gotten what you deserve. I guess you found out it's dangerous to be a busybody. Stop wringing your hands, Sit don and let me wring your heart instead, which I will do if it's still soft enough, if your evil lifestyle has not toughened it against feeling anything.
Hamlet is debating if he should kill himself. He's trying to decided if it's better to suffer through life and being miserable or just end it and risk the unknown. He knows it's sin so he decides its better to just suffer through life.
Here Hamlet is keeping himself from killing the king because he doesn't want him to die while he's confessing his sins because he doesn't want him to go to heaven. This shows just how much he wants Claudius to suffer and to get his revenge.
This shows how cold Hamlet has become. I don't think he would have killed Polonius if he know it was him but after he killed him he didn't even feel sorry. He blames it on him and said he deserved it and then right after continues to make sure he made his mom feel bad and it shows just how cold and hard he's become trying to avenge his father.