Chillingworth changes in the physical and the personal aspects of being throughout the novel.
We first see Chillingworth as the stranger in Chapter 3, appropriately named The Recognition. He is described as:
... a white man, clad in a strange disarray of civilized and savage costume.
Then, moments later, further physical and personality traits are revealed:
He was small in stature, with a furrowed visage, which, as yet, could hardly be termed as aged. There was remarkable intelligence in his features, as of a person who had so cultivated his mental part that it could not fail to mould the physical to itself...
... the stranger had bent his eyes on Hester Prynne. It was carelessly, at first, like a man chiefly accustomed to look inward, and to whom external matters are of little value and import, unless they bear relation to something within his mind... his look became keen and penetrative.
During this third chapter, the man is described as intelligent and certainly not old. His physical appearance may be one which demonstrates understanding of different cultures and values. The look on his face at recognition of Hester desmonstrates great thought, as if he has studied man like he has studied books.
By the 4th chapter, Chillingworth alludes to his growing age and the deformity he has compared to a young girl like Hester. He understands that all the time he put into his career and intellectual life also gave him the belief that he could make a woman like her want him.
By chapter 9, Chillingworth is finally well adapted to this society, and rather welcomed. He had great medicinal skill as people noted that he gathered herbs they assumed for medical use. Chillingworth in conversation with the young minister is described as:
the man of skill, the kind and friendly physician [who] strove to go deep into his patient's bosom, delving among his principles, prying into his recollections, and probing everything with a cautious touch.
He is also regularly referred to as "old Roger Chillingworth" throughout the text.
By chapter 10, Chillingworth's efforts to work with Dimmsdale reveal a most serious change in his personality for
Old Roger Chillingworth, throughout life, had been calm in temperment, kindly... and in all relations with the world, a pure and upright man... as he proceeded (with his investigation of Dimmsdale), a terrible fascination, a kind of fierce necessity seized the old man within its grip, and never set him free... He now dug into the poor clergyman's heart, like a miner searching for gold.
Over the course of the novel up until chapter 12, Chillingworth's image begins to look increasingly hideous. He looks older and his face continues to contort as he learns of what ails Dimmsdale. In terms of his mental state, he has always been particularly able to see into the hearts of mankind. As the novel continues, his pursuit to practice this skill goes from being rather kind about his psychological ability to rather psycho about this kind of ability. He grows angry and determined instead of naturally curious.
SHe just aboutt took all i had to say, i am studying this book as we speak!(: