John Proctor is one of my favorite characters in literature because he is a good man who wrestles with his sins yet eventually finds freedom and forgiveness through his faith. In the meantime, though, he is a conflicted man.
The most obvious conflict, of course, is his broken covenant with his wife Elizabeth. He has had an illicit relationship with Abigail, someone he clearly never loved. His feelings of guilt and shame torment him, for he knows he has broken faith with someone he does love.
He's also been untrue to God. He is, despite his protestations and stubborn resistance to Reverand Parris, a godly man who is concerned about the condition of his soul. Proctor's covenant with Elizabeth was made before God, and he is aware of the sullied condition of his soul.
Another conflict Proctor has is with the town of Salem. He is a practical man, and the town seems to have gone down a path of religious fervor unconnected to true faith. He has no patience for fancy candlesticks or scare tactics to intimidate sinners out of hell. Despite that, he understands he should be connected to a church body on a regular basis and is struggling to find a way to do that.
Proctor is conflicted about confessing to something he isn't guilty of, to someone (the court) he has no respect for, in order to save his life and stay with the family he loves. It's true he has done nothing to warrant this specific sentence and punishment; however, he has committed the sin/crime of adultery and feels as if he should be punished for that. Therein lies the conflict: I didn't commit this sin, he reasons, but I did commit the other; so I'm not innocent. He really tries to compromise, but he understands his good name (his honor and character, his very soul)) will be restored only if he accepts this fate. It's a crisis of the soul, and he is able to find redemption through maintaining his integrity in the face of injustice.
John Proctor is a flawed character, fighting many serious inner conflicts; however, he finds peace as he asks forgiveness of his wife, his God, and himself.