Reverend Hale undergoes a dramatic transformation between Act I and Act III. Arriving in Salem as an authority on witchcraft, he becomes a vital member of the court, assisting in the process of uncovering witches that are present in the village. Reverend Hale participates in the condemnation, along with the court, and signs off on the execution of 12 people.
As the play progresses, particularly after John Proctor is arrested, Reverend Hale begins to see that the accusations of witchcraft are being used as a tool of vengeance in the town. He begins to doubt Abigail Williams testimony and when she is revealed to be a harlot, for having an adulterous relationship with John Proctor, Reverend Hale no longer believes that there are any witches in Salem. He leaves the court and returns home.
At the end of the play, Reverend Hale returns to Salem with one purpose and one purpose only, to save as many of the accused as possible. He goes about this process by begging those awaiting execution to confess to witchcraft in order to save their lives.
His change has occurred as a result of a long period of meditation and fasting, he believes, now, that he is actually working for God, by trying to save innocent people from wrongfully being put to death for a lie. He particularly wants to save John Proctor's life, but is unsuccessful.