Analyze Roger Chillingworth in literary terms.

Chillingworth is to a degree a symbol of the hypocrisy and generally negative forces Hawthorne identifies in the society of the seventeenth-century New England Puritans.
Though Hester and Dimmesdale have "sinned," the author's point is that Chillingworth, in methodically seeking vengeance, is committing a far worse moral error than they have. Theirs is a lapse in judgment rooted in passion; his is conscious, deliberate, and planned. Yet, as in all of Hawthorne's works, in The Scarlet Letter there is no clear-cut definition of good and evil. Chillingworth appears as a decrepit figure who, in spite of his wily plotting, is more pathetic than evil. In addition, if he brings about Dimmesdale's confession, in some sense Chillingworth can be seen as a kind of redeemer in disguise; this point, if valid, is emphasized by the fact that Chillingworth himself does not survive the story.
One does not know if the ambivalence that seems to be expressed by Hawthorne throughout his fiction is a kind of cover of, or attempt to disguise, the radical nature of his own free-thinking mindset, which would have been unacceptable to many people even in the more enlightened nineteenth-century world. Though both Hester and Dimmesdale emerge as Christ-like figures in the story, the figure of Chillingworth, though an enemy and an antagonist to both of them, cannot be explicitly analogized to the devil or to any other supernatural agent of evil. Hawthorne's point, as always, is that rigid moralistic thinking is wrong and self-destructive. At bottom, The Scarlet Letter is above all a human story that exists in a higher dimension than that of the religious condemnations and divisive forces of the time period in which it is set.