Final answer:
Dimmesdale forgives Hester because he sees himself as a worse sinner than she is. He believes that he is a hypocrite and a fraud for preaching about morality while hiding his own transgressions. By forgiving Hester, Dimmesdale seeks to alleviate some of his guilt and share in her burden of shame.
Step-by-step explanation:
Dimmesdale forgives Hester because he sees himself as a worse sinner than she is. In Nathaniel Hawthorne's novel, The Scarlet Letter, Dimmesdale is the town's revered minister who has committed adultery with Hester. However, while Hester publicly bears the shame and punishment for their sin, Dimmesdale carries the guilt and torment internally.
In his own mind, Dimmesdale sees himself as a hypocrite and a fraud. He preaches about morality and righteousness while hiding his own transgressions. This inner conflict leads Dimmesdale to suffer physically and psychologically, as seen in his sickly appearance and self-inflicted penance.
Dimmesdale's forgiveness of Hester can be seen as an act of empathy and self-awareness. He recognizes that both he and Hester share in the guilt of their sin, but Hester has taken the brunt of the public shame. By forgiving Hester, Dimmesdale seeks to alleviate some of his own guilt and share in her burden of shame.