Reverend Hale is trying to understand the situation he is in. He has been surprised by the accusation against Rebecca Nurse, having accepted her as an intelligent and well-read person, like himself. He isn't sure what to make of the Proctors, and does not understand why they would avoid attending church. It is in this scene that John Proctor speaks out against Rev. Parris, criticizing the man for hypocrisy and explaining his avoidance of church revolves around that, and not his belief or disbelief in God.
Hale still believes in his quest here, especially when he first arrives at the house. However, unlike the townspeople, he has an open mind, and his visit with the Proctors begins to tear at what few doubts he does have. He goes in order to find truth - it just isn't the truth he thought he would find.