Hester tells Dimmesdale that the man living with him is actually her husband. She advices him to leave town, change his name, and start a new life. Dimmesdale is hesitant. He does not believe that he is worthy of relief from his guilt. He feels his only redemption lies in remaining at his post trying to save the souls of the people of the town. In the end, he agrees to leave if Hester and Pearl come with him.
Some useful quotes:
Hester: "So brief a journey would bring thee from a world where thou hast been most wretched, to one where thou mayest still be happy!" .... "Give up this name of Arthur Dimmesdale, and make thyself another, and a high one, such as thou canst wear without fear or shame."
Dimmesdale: "I am powerless to go. Wretched and sinful as I am, I have had no other thought than to drag on my earthly existence in the sphere where Providence hath placed me. Lost as my own soul is, I would still do what I may for other human souls! I dare not quit my post, though an unfaithful sentinel, whose sure reward is death and dishonour, when his dreary watch shall come to an end!"\
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