about Elizabeth's justice.  He tells her that her justice "would freeze beer."  That's a really cold and hurtful comment, but what I like about it is that it actually references a cold temperature.  Beer has alcohol in it, which lowers the freezing point of beer.  Beer must be cooled below water's freezing point to freeze.  That's cold, and that's why John's comment is literally and figuratively a cold comment.  

John Proctor is a good man according to his wife, yet we know from the opening of The Crucible that Proctor has had an affair with Abigail Williams. He suffers in his sense of guilt and works diligently to make amends to Elizabeth. 

Elizabeth finds true forgiveness very difficult. She cannot believe her husband when he says that the affair is over and she cannot forget the harm that has been done to her. Proctor desires only forgiveness from her so that the two can move on and find some semblance of normalcy again. 

When Elizabeth continues to act accusingly, Proctor finally claims that she is being cold to him. He says that she neither forgives not forgets and that her "justice would freeze beer". Proctor accuses Elizabeth of looking only to judge him and not attempting to see the goodness in him. 

In the crucible, the court realized that what they were doing was a mistake. They were condemning innocent people to death based on lies told by the girls. Paris brought news that Abigail was gone and that she stole some of his money. These issues rested heavily on those who were falsely accusing the people of witchcraft. However, Mr. Danforth sought to protect the court’s reputation and so could not free the innocent people in spite of knowing the truth.

They summoned Elizabeth to convince her husband, John, to confess to witchcraft. When the couple met, John found out some of the people had already confessed. However, some of his friends refused to comply. He sought his wife’s opinion on whether he should confess to the fake charges against him. He blamed himself for being unfaithful to Elizabeth and even sought her forgiveness. It was at that moment that Elizabeth presented a confession of her own. She blamed herself for pushing John into lechery and admitted to not providing a loving and caring environment for her husband.

Elizabeth: I have sins of my own to count. It needs a cold wife
to prompt lechery.

Elizabeth: You take my sins upon you, John -
Proctor, in agony: No, I take my own, my own!
Elizabeth: John, I counted myself so plain, so poorly made, no honest love could come to me! Suspicion kissed you when I did; I never knew how I should say my love. It were a cold house I kept! In fright, she swerves, as Hathorne enters.

The confession that Elizabeth makes to John in Act IV is that she realizes that she herself played some role in the marital difficulties that led John to commit adultery with Abigail.  She states that "it needs a cold wife to prompt lechery.." and continues that

I counted myself so plain, so poorly made, no honest love could come to me! Suspicion kissed you when I did.  I never knew how I should say my love. It were a cold house I kept.  (Act IV scene 2)

In this admission Elizabeth has shown great growth in character and is no longer the suspicious fragile woman she once was.

In Act IV of The Crucible by Arthur Miller, John Proctor sits in jail because he has been condemned for practicing witchcraft. He will be hanged unless he confesses to the crime. Consequently, his wife Elizabeth visits him and tries to convince him to confess so the court will spare his life.

John does not confess -- for the charge is false -- but he begs Elizabeth to forgive him for committing adultery with Abigail. Elizabeth then makes a confession of her own: she was suspicious of John and Abigail, but she did not confront him. Consequently, she holds herself responsible for John being caught up in the witchcraft hysteria in Salem.

Moreover, Elizabeth blames herself -- at least partly -- for John's decision to cheat on her, as shown in this excerpt: 

I have sins of my own to count.  It needs a cold wife to prompt lechery...I counted myself so plain, so poorly made, no honest love could come to me!  Suspicion kissed you when I did; I never knew how I should say my love.  It were a cold house I kept.

Elizabeth believed if she had been more openly affectionate toward John, he would not have committed adultery and subsequently been accused of witchcraft.

Elizabeth and John are allowed one more chance to speak to each other before John is taken to be hanged.  The judges allowed this in the hopes that Elizabeth would convince John to confess to witchcraft to save his life; the townspeople were starting to turn on the courts for all of the deaths, and they hoped John confessing and not dying would convince others to do the same.

So, John and Elizabeth speak one last time.  In their very touching conversation, John begs Elizabeth's forgiveness for his adultery.  He has been tormented with guilt, and left to sit in jail and ponder his life for months now.  As he asks her for forgiveness, Elizabeth confesses her own part in the situation.  She confesses,

"I have sins of my own to count.  It needs a could wife to prompt lechery...I counted myself so plain, so poorly made, no honest love could come to me!  Suspicion kissed you when I did; I never knew how I should say my love.  It were a cold house I kept."

In this heart-rending "confession," Elizabeth admits that she was not a very loving wife.  She was cold to him, suspicious, and never spoke of her love for him.  She did this because she had low self-esteem, and considered herself ugly and unlovable.  So, she didn't even try.  This admission sheds some light on their marriage, and also on her potential role in John's affair.  They end up both forgiving each other, and for the first time in a long, long time, feel close and reconciled; unfortunately, it is just as John goes to die.  I hope that helped a bit; good luck!