Chapter 9 of Nathaniel Hawthorne’s The Scarlet Letter is titled “The Leech.” This title tells the reader a lot about the primary antagonist in the novel, Roger Chillingworth. As a leech lives by feeding off the blood of another, Chillingworth, under the guise of a physician, is going to devote his life to secretly undermining and torturing Reverend Arthur Dimmesdale.
Hawthorne’s intent, however, is not immediately evident. Most of the chapter discusses the budding relationship between Chillingworth and Dimmesdale. It sounds like they will grow to be good friends who have a positive effect on each other. In fact, Dimmesdale appreciates Chillingworth’s intelligence and education:
"There was a fascination for the minister in the company of the man of science, in whom he recognized an intellectual cultivation of no moderate depth or scope, together with a range and freedom of ideas that he would have vainly looked for among the members of his own profession."
In other words, Dimmesdale is able to discuss ideas with Chillingworth that he can’t discuss with others in the clergy.
Then, in the next paragraph, Hawthorne describes Chillingworth, in his role as Dimmesdale’s doctor, this way:
"So Roger Chillingworth—the man of skill, the kind and friendly physician—strove to go deep into his patient’s bosom, delving among his principles prying into his recollections and probing everything with a cautious touch, like a treasure-seeker in a dark cavern."
It is at the end of the chapter that Hawthorne fully develops the contrast between the two men that will continue throughout the rest of the novel. A number of the townspeople began to suspect false motives on Chillingworth’s part:
". . . it grew to be a widely diffused opinion that the Reverend Arthur Dimmesdale, like many other personages of especial 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."
Here we see that the public perception of Chillingworth is intuitively on target--they can see through him as Dimmesdale does not. Conversely, and this illustrates the contrast between the two, Dimmesdale is nearly idolized by his parishioners:
"The young divine [Dimmesdale], whose scholar-like renown still lived in Oxford, was considered by his more fervent admirers as little less than a heavenly-ordained apostle, destined, should he live and labor for the ordinary term of life, to do as great deeds for the now feeble New England Church, as the early Fathers had achieved for the infancy of the Christian faith."
The final sentence of the chapter clearly lays out the conflict that will unfold over the next 14 chapters:
"Alas! to judge from the gloom and terror in the depths of the poor minister’s eyes, the battle was a sore one, and the victory anything but secure."
Hawthorne here is saying that Dimmesdale’s battle against the guilt that is eating him alive, spurred on by the physical and mental warfare secretly being waged by Chillingworth, is no sure thing—he might not win. In fact, he only partly wins the battle. He does find redemption at the end of the story, but it is only as he succumbs to death, leaving Hester and his daughter Pearl behind to face the world without him.