John Proctor, our main character, is in desperate need of forgiveness at the start of the play, but his wife seems torn about whether to grant it. He had committed adultery earlier that year while she was sick, and though his lover Abigail Williams is now out of his life, she still judges him for it. More importantly, he still judges himself. It isn’t until Elizabeth forgives him, and admits her own fault in the matter, that John Proctor is able to forgive himself and recognize some goodness left in him. It is also what gives him courage to go to his death.
Even though John Proctor wants his wife’s forgiveness, he actually needs to forgive himself, just like she says.
Although Elizabeth Proctor argues that John is his own worst judge and needs to forgive himself, she is justified to think that he is still not completely faithful in his heart.