No reader should ever discount the significance of titles or the names of the characters in a novel because they have always been selected carefully by its author. Such is truly the case in considering the characters' names of Nathaniel Hawthorne's The Scarlet Letter.
The Reverend Arthur Dimmesdale
This paradoxical name is a clue to the conflicts that lie within the minister. While he has the potential to be a strong, passionate man--Arthur, suggestive of the legendary king--the Puritan minister does not have the fortitude to come forward in Hester's defense in Chapter II and join her on the scaffold. He rationalizes harboring his secret sin, telling himself that he serves God and the community better by continuing as their minister. But, his hypocrisy in concealing his secret sin, eats at him, diminishing his mental and physical strength. Vulnerable to the machinations of the vengeful Roger Chillingworth, Dimmesdale's spirit "dims" and he weakens to the point that when he does confess his sin, he expires.
In his forest meeting with Hester, Arthur Dimmesdale is so weak and "dim" that it takes Hester's courage and strength to enliven him. Encouraged by Hester's stalwart personality, Dimmesdale finds the courage to finally confess his sin and to stand with his family on the scaffold where he belonged long ago. In his confession he does give humanity to his daughter Pearl, who kisses her father and is made complete. Thus, he exemplifies some of the forthrightness and bravery of his namesake, Arthur.
[See Chapters 10,12, 16-18]
To sum up the matter, it grew to be a widely diffused opinion, that the Rev. Arthur Dimmesdale, like many other personages of special sanctity, in all ages of the Christian world, was haunted either by Satan himself, or Satan's emissary, in the guise of old Roger Chillingworth. This diabolical agent had the Divine permission, for a season, to burrow into the clergyman's intimacy, and plot against his soul. No sensible man, it was confessed, could doubt on which side the victory would turn.... it was sad to think of the perchance mortal agony through which he [Dimmesdale] must struggle towards his triumph.
Alas, to judge from the gloom and terror in the depth of the poor minister's eyes, the battle was a sore one, and the victory any thing but secure!
This passage from the end of Chapter IX enlightens the reader to the formidable enemy that the Reverend Dimmesdale faces. Roger Chillingworth is a frightening man who has insidiously worked his way into the home of the minister as well as the interior of Dimmesdale's mind and spirit.
In Chapter X, "The Leech and His Patient," Hawthorne writes that Dimmesdale "could not recognize his enemy when the latter actually appeared." Because of this situation, Chillingworth's actions are indeed disturbing. Having told Hester in his interview with her in Chapter IV that the man who has fathered her child "will be mine," the demonic Chillingworth violates the integrity of the human heart as he delves into the interior of the minister's soul by asking penetrating questions in Chapter X. When the emotionally exhausted minister falls asleep, Chillingworth secretly pulls away the vestment of the minister in order to reveal his chest. With a "ghastly rapture" Chillingworth comports himself like Satan who has stolen a soul.
Later, in Chapter XIV, it is a hunched and blackened man that Hester encounters, a "fiend" by his own admission.