Proctor is not only concerned with Elizabeth, but he is also concerned with the truth. Elizabeth is not the only accused that John knows. If the girls are allowed to get away with lying, then the others will also be condemned. In addition, as shown by the last scene, Proctor is also concerned with his own credibility. He does not want to be seen as a liar whose only concern was his wife. He wants the court to take his charges seriously because he knows they are true. He wants to be known as a man of truth so in the future people, including his children, will also believe him.