How has Chillingworth changed since Hester last saw him?

Chillingworth is several years older than the last time he and Hester were together, and when she sees him in the crowd, he is dressed in "a strange disarray of civilized and savage costume."  Probably due to his time with the Native Americans, he wears a combination of his own European attire and native garments.  Further, when they meet face to face in the jail, he "entered the room with the characteristic quietude of the profession to which he announced himself as belonging."  He has told the jailer that he is a doctor, and the year that he's spent with the Native Americans has allowed him to become well-versed in the medicinal properties of herbs and plants. 

Moreover, Hester expects Chillingworth to be very angry and possibly attempt to harm herself or her child; however, he actually seems to want to help them, especially the baby, and takes some responsibility for his and Hester's inappropriate marriage.  He sees, now, that it was his "folly," as an older man with little to offer a young bride, to compel her family to allow him to marry her.  In other words, he seems somewhat less proud and a more compassionate than she expects, leading us to believe that these are changes from the man he used to be.  On the other hand, when he vows vengeance on the man who Hester had her affair with, she wonders if he is the "Black Man," or devil, because of the changes that seem to take place on his face and in his address.