The Reverend Parris is one of the primary characters in Arthur Miller's The Crucible, and his moral development throughout the course of the play is questionable.
We first meet him at the side of his young daughter's bed, apparently praying for her to be healed; what we soon discover, however, is that his motivation for wanting Betty to wake up is that it will reflect poorly on him is she does not.
Parris is an arrogant man who does not act like a true minister of God in many ways. He is overly concerned about his reputation and about money, neither of which are attributes of godliness by most definitions. These are the things everyone can see; what is hidden is that he, too, was in the forest last night. He does not appear to be a man of God in anything but name. He is also paranoid and worries that people in town are conspiring against him.
Parris: Abigail, do you understand that I have many enemies?
Abigail: I have heard of it, uncle.
Parris: There is a faction that is sworn to drive me from my pulpit. Do you understand that?
Unfortunately, Parris is at the center of the witch trials, and he tirelessly shifts blame to those against whom he holds a grudge (especially John Proctor).
The test of his moral development is whether he is the same weak man at the end of the play as he was at the beginning, and the answer is mostly yes.
It is true that he shows up at the prison on the day of the hangings to pray with the prisoners, but he is too busy whining about Abigail's absconding with his money and neighbors who have threatened him to do any real good. It is obvious he is here for himself, not for the prisoners whom he helped condemn. The stage directions say "He chokes up," but it is at his own woes, not the prisoners'. His prayers with them are ineffectual.
It is also true that he realizes Abigail has lied to him; however, he had to have known she was pretending during the proceedings and did not say anything because what she was doing was to his benefit, as well.
Parris may have had a few moments throughout the play which display a bit of moral development, but it is minimal, at best. The truth is that most of what motivates Parris at the end of the play is the same as what moves him at the beginning--himself.