It is important above all to identify what Angel Clare as a character represents and how his actions illustrate the kind of person that he is. We are told that he was brought up in a rural family where his father was a pastor. He, instead of conforming like his brothers and seeking to go and study at Cambridge, is fixed on becoming a farmer. His character therefore is representative of somebody who rebels against society and its expectations towards his own idea of what it is to pursue goodness. His desire is to labour on behalf of the "honour and glory of man" in the here and now rather than for eternal benefits.
He is a progressive character and looks upon the world with the eye of improving it and bettering it for all concerned, as he believes that man is essentially good and noble. The way that he falls in love with Tess, a mere milkmaid who is well below him socially, is a sign of his disdain for social conventions and propriety. He seeks to make his own way in life and live his life uninhibited by the expectations of those around him.
Angel Clare, while seemingly rebellious, is actually very much a product of his upbringing. In fact, he is even more intolerant than his father and mother, who are presented as being kind and compassionate, though traditionally religious.
He falls in love with Tess at the dairy farm. He sees her through a romantic lens--as a pure, innocent, naive milkmaid. He convinces her to marry him. Tess knows that he will not accept her secret past--a rape and a baby who died in infancy. But her love for Angel Clare overcomes her misgivings, and she decides to marry him anyway. On the wedding night, Angel Clare confesses that he is not a virgin. Tess, suddenly feeling liberated, tells Angel about her past.
His response is to leave her. He tells her that he cannot love her knowing what he knows about her. With only a bit of money, Tess is put out on her own. She is impoverished and suffers greatly, doing hard labor in order to survive.
Angel Clare, though, is a dynamic character. He changes. He goes to South America, becomes very sick, and begins slowly to understand what is important in life. When he gets away from England, he is able to get a better perspective on his values and his decisions. He rediscovers his love for Tess and returns to England to claim her.
Of course, it is too late, for in extreme desperation she has married Alec. Yet, Angel Clare is able to accept Tess once again--even if she is a murderer. Perhaps more than any other character, Angel Clare grows in the novel. He changes from a wantabe rebel to a man who is willing to risk everything for the woman he loves.