When John Proctor comes to court in the Act III of The Crucible by Arthur Miller, his purpose is to denounce the girls and their fakery and to set his wife free.  He has three weapons that he plans to use in the court to prove the falsity of the claims against all of those who have been imprisoned. 

His first plan is to relate to the court Abigail’s admission to him that there is no witchcraft and that Betty Parris was faking her trances.  Proctor’s admission will debunk Abigail in the eyes of the court and discredit the other girls since she is their leader.

In addition, he has enticed Mary Warren to give her testimony that she and the other girls have not been witched and have been pretending when they go into their spells. Finally, Proctor plans on admitting that he and Abigail had an affair which will establish that she holds a grudge against Elizabeth Proctor for turning her out of Proctor’s house.

All of his weapons fail, particularly when Elizabeth denies that John had an affair with Abigail just after Proctor had admitted it. Proctor’s mistake was in thinking that this was a true court looking for guilt or innocence or the truth. 

He intends to take the place of his wife with his own guilt and in doing so bring down Abigail as well.  What he discovers is a court that has already hanged people and signed death warrants for others. If they back down now, it will subject the judges and the court to ridicule. In the course of the chaos during Proctor’s and Mary Warren’s testimony, Reverend Hale finally begins to admit that these are ridiculous accusations, brought about by a group of foolish, school girls.

Rev. Hale begins to try to defend Proctor,  aware that he is telling the truth.  The coup de grace for Proctor happens when he tries to touch Mary Warren and she accuses him of witchcraft which ends any possibility of the court listening to him.   Danforth issues an arrest warrant for Proctor and asks Proctor is he will confess. Proctor announces that he believes that God is dead which will of course damn him before the court.

PROCTOR, laughs insanely, then: A fire, a fire is burning! I hear the boot of Lucifer, I see his filthy face! And it is my face, and yours, Danforth! For them that quail to bring men out of ignorance, as I have quailed, and as you quail now when you know in all your black hearts that this be fraud – God damns our kind especially, and we will burn, we will burn together!

In this quotation, Proctor’s guilt that he has let his family down issues forth.  Obviously, Proctor is the better man than all of the court.  He is more honest and moral.  Danforth cares not for the truth but rather for the reputation of his court.

Proctor places himself on an even par with Danforth and the court.  He cannot forgive himself for the harm that he has done to Elizabeth. Proctor says that he has hesitated to come to court and tell the truth. 

Now, Proctor knows that all of the judges know that he is telling the truth, and they are afraid to admit it. Proctor denounces them and states that In their hearts, they know the truth and will not give up to it because the devil lives within them.  He damns himself and the court saying that they will be punished together in hell for their actions. 

When Mary Warren first appears in The Crucible, the stage notes indicate that she's "seventeen, a subservient, naïve girl." Mary Warren is modeled after the historical Mary Ann Warren, born in Salem in 1674 or 1675, who was a servant to John and Elizabeth Proctor.

Prior to and during the actual witch trials, the historical Mary Warren made accusations of witchcraft against people in the Salem community, including Giles Corey—also a character in The Crucible—whom she accused of appearing to her as a ghost. When Mary herself was accused of witchcraft, she turned on John and Elizabeth Proctor and accused them of witchcraft.

In The Crucible, Mary Warren's subservience and loyalties change through the course of the play. At first she's subservient to John and Elizabeth Proctor, for whom she's employed as a servant. Her subservience and loyalty shift to Abigail Williams, the ringleader of the group of girls at the center of the accusations of witchcraft toward others in the community. Finally, Mary is loyal only to her own interests and self-preservation when she's accused of witchcraft, and she accuses others of witchcraft to save herself.

In The Crucible, Mary's first "victim," whom she apparently accuses of witchcraft reluctantly and unwittingly, is Sarah Good, a destitute, sixty-year-old woman considered an outsider by the Salem community.

In act 1, scene 2, Mary tells John Proctor about her experience at the trials that morning, which John Proctor had forbidden her to attend.

MARY. (Innocently.) I never knew it before. I never knew anything before. When she [Sarah Good] come into the court I say to myself, I must not accuse this woman, for she sleep in ditches, and so very old and poor...But then...then she sit there, denying and denying, and I feel a misty coldness climbin‘ up my back, and the skin on my skull begin to creep, and I feel a clamp around my neck and I cannot breathe air; and then...(Entranced as though it were a miracle.) I hear a voice, a screamin‘ voice, and it were my voice...and all at once I remembered everything she done to me! (act 1, scene 2)

In act 2, Mary decides to tell the truth to Deputy Governor Danforth, who's conducting the trial, that she and the other girls were simply pretending when they said that they saw spirits and acted as if they were attacked by witches.

DANFORTH. And you, Mary Warren...how came you to cry out people for sending their spirits against you?

MARY. It were pretense, sir.

DANFORTH. (With great unbelief.) Ah? And the other girls? Susanna Wallcott, and...the others? They are also pretending?

MARY: Aye, sir (act 2, scene 2).

When Danforth confronts Abigail about this, she denies it and instead acts as if she's being attacked by Mary's spirit in the form of a freezing wind, and then she acts as if Mary's spirit is a "yellow bird" sitting in the rafters, intending to attack Abigail's face. Soon the other girls in the room take up the pretense, and all of them cry out against Mary.

Mary, hysterical with fear, backs away from John Proctor, who is trying to help her, and accuses him to save herself.

MARY. (Pointing at Proctor.) You are the Devil‘s man!...I‘ll not hang with you! I love God, I love God—....(Hysterically, indicating Proctor.) He come at me by night and every day to sign, to sign, to...

DANFORTH: Sign what?

PARRIS: The Devil‘s book? He come with a book?

MARY: (Hysterically, pointing at Proctor.) My name, he want my name; I‘ll murder you, he says, if my wife hangs! We must go and overthrow the court, he says...!

...(Her sobs beginning.) He wake me every night, his eyes were like coals and his fingers claw my neck, and I sign, I sign....

(Screaming at him.) No, I love God; I go your way no more, (Looking at Abigail.) I love God, I bless God....(Sobbing, she rushes to Abigail.) Abby, Abby, I‘ll never hurt you more! (All watch, as Abigail reaches out and draws sobbing Mary to her, then looks up to Danforth) (act 2, scene 2).

John Proctor is led away to jail and is accused of witchcraft.

Choosing Elizabeth Proctor's most important quote is left up to individual readers; therefore, the answer to this question is subjective. I like the following lines from act 2.

It is her dearest hope, I know it. There be a thousand names; why does she call mine? There be a certain danger in calling such a name—I am no Goody Good that sleeps in ditches, nor Osburn, drunk and half-witted. She’d dare not call out such a farmer’s wife but there be monstrous profit in it. She thinks to take my place, John.

This is an important quote from Elizabeth to John, because she flat out gives John a legitimate reason for why Abigail is doing what she is doing and why she would give Elizabeth's name. John did commit adultery with Abigail, and John believes that he has adequately ended all possible relations with Abigail; however, Elizabeth gently explains that Abigail sees his physical intimacy as a promise to her. Elizabeth correctly points out that Abigail is motivated by jealously and selfish gains.

I also think the following lines are also important from Elizabeth.

John, it come to naught that I should forgive you, if you'll not forgive yourself. It is not my soul, John, it is yours. Only be sure of this, for I know it now: Whatever you will do, it is a good man does it. I have read my heart this three month, John. I have sins of my own to count. It needs a cold wife to prompt lechery.

[...]

Do what you will. But let none be your judge. There be no higher judge under Heaven than Proctor is! Forgive me, forgive me, John—I never knew such goodness in the world!

John has worked very hard to earn back Elizabeth's trust in him. He desperately seeks her forgiveness, but she has been averse to fully giving it. Here we see that she openly forgives John, and we see her confessing her own sins to her husband. Her forgiveness and honesty causes John to seek his life and confess. He wants to be with Elizabeth and his family even if it means living with his lie.

I consider her very last line, and the last line in the play, the most important.  In speaking of John's decision to be hanged to preserve his honor, she says, "He have his goodness now.  God forbid I take it from him!"  This connects with a recurring theme in the book, which is John's struggle to feel like a worthy, good man.  He loathes his sin with Abigail, and feels that he is "not worth the dust on the feet of them that hang!"  He had just said that "My honesty is broke, Elizabeth; I am no good man."  However, in choosing to die, he earns his goodness back, and Elizabeth sees this.  She fights through her desire to have her husband back, alive, and with her after a very touching reconciliation, and instead declares that in ensuring his doom, he also ensured his own peace of mind and goodness.  It takes a strong woman to do that, and shows the true grit of her character.

Mary Warren is an interesting character. She is timid and easily manipulated by John and Abby, but she does stand up for herself at times. Like John, Mary is constantly conflicted by the opposition of doing what's right and saving herself.

In Act 1, Mary pleads with Abby to cut the charade so they don't get into any more trouble. "Abby, we've got to tell. Witchery's a hangin' error, a hangin' like they done in Boston two years ago! We must tell the truth, Abby! You'll only be whipped for dancin', and the other things!"

In Act 2, Mary returns from the court proceedings to inform the Proctors of what has transpired. She also leaves a doll (poppet) at their house which Abby will later use to incriminate Elizabeth. "I made a gift for you today, Goody Proctor. I had to sit long hours in a chair, and passed the time with sewing." Despite Mary's attempts to come clean, she has been persuaded by Abby to engage in conspiring to incriminate Elizabeth. However, Mary does later admit to the Proctors and Hale that the poppet is hers. Following this episode, the end of Act 2, John orders Mary to go with him to court.

At the beginning of Act 3, Mary admits to the court (Danforth and others) that the girls had lied (pretense) when they accused others of "sending their spirits" against the girls.

Later in Act 3, Danforth asks Mary to pretend to faint to prove she can repeat this pretense. Mary is so bewildered she can't bring herself to do it. She provides one of the best descriptions in the play of how one (Mary) can become caught up in the hysteria/mob mentality.

It were only sport in the beginning, sir, but then the whole world cried spirits, spirits, and I--I promise, you, Mr. Danforth, I only thought I saw them but I did not.

At the conclusion of Act 3, Abby and the other girls pretend that Mary is sending her spirit on them. Terrified and desperate to save herself, Mary again is manipulated by this outburst from the girls. She shifts the blame to John Proctor. "I'll murder you," he says, "if my wife hangs! We must go and overthrow the court," he says!"

Mary is a relatively sympathetic character because John and Abigail use her like a pawn. She is at the mercy of their manipulations and therefore feels forced to bounce between truth and lies.

Mary Warren went to the courts in act three determined to confess that she and the girls were merely pretending.  John Proctor helped to convince her to do this, because he is desperate to get his wife, Elizabeth, freed.  Mary knows that it is all a fraud, but thus far has been too chicken to come forward and state it.  She is worried that if she does, "they'll turn on me," as she says in act two, meaning, Abby and the other girls will accuse HER of being a witch.  Mary is terrified of this accusation; she knows what power Abby has over the courts, and that if she crosses Abby, Abby will take revenge on her.  Mary doesn't want to be accused of being a witch; she fears it and avoids it at all costs.

However, after Elizabeth Proctor is arrested on the ridiculous claim that she stabbed Abby in the belly with a needle, John convinces Mary to be brave and tell the courts that she and the other girls are all pretending.  And, she tries to do this, she really does.  She gets up there, tells the judges that "it were all pretense" and tries to explain how that could be.  After the judges turn on her and command her to faint, she says that she can't, that she's all alone, and when she fainted in the courtroom all of the other girls were screaming and fainting "and you seemed to believe them," and so she got caught up in the mass hysteria of it all.  However, as soon as the judges start listening to Mary, Abby turns on her.  Abby starts pretending to be super scared, and to see a "yellow bird" that is supposedly Mary's spirit, that wants to come down and pluck her eyes out.  All of the other girls follow suit, and pretty soon Abby has the judges believing that Mary is sending her spirit out to attack her.  Mary sees how Abby has turned the judges against her, and because she fears being accused of being a witch, she denounces her previous claims of having pretended, and accuses John of influencing her.

So, instead of sticking to her guns and being brave, Mary, in order to get out of being accused of being a witch, turns on John and calls him a "devil's man" who came to her and forced her to sign his "black book" and told her that she must come to the courts to overthrow them.  As soon as she does this, Abby stops with the ridiculous (and fake) bird act, and accepts Mary back into her good favors.  John ends up being accused of witchcraft, and Mary saves her own neck.

I hope that clears things up for you a bit; it's a confusing scene with lots going on in it, so I hope that helps.  Good luck.

Mary Warren initially went to the court to confess that she and the girls had been pretending.  However, just as she had predicted at the end of Act  Two ("They'll turn on me!  I cannot!"), Abby and the girls did in fact turn on her.  They cried out, insisting that Mary's familiar spirt came into the courtroom in the form of a yellow bird that was going to claw Abby's face.  Judge Danforth immediately picks up on the cue, and asks Mary if she is a witch, and asks John if he is somehow forcing Mary to turn on the girls.

When Danforth suggests Mary will hang for being a witch, Mary finally caves, and turns on John, calling him a "Devil's man" (look at the very, very end of Act Three for the quotes you need) who had come to her with his black book to sign, and forced her to come to the courts to overthrow them.  This is truly sad, as she was the last thread of hope that Proctor had for saving his wife and friends.

Arthur Miller's play "The Crucible" is filled with revenge and fear. The fear that the villagers feel bring about a mass hysteria ending in the persecution and death of many whom have been charged with being witches. Throughout the play there are many poignant quotes which one could focus upon in essays.

The first quote one could scrutinize for analysis purposes is

I look for John Proctor that took me from my sleep and put knowledge in my heart! I never knew what pretense Salem was, I never knew the lying lessons I was taught by all these Christian women and their covenanted men!

This quote is found in Act One and is spoken by Abagail Williams. Prior to the action of the play, readers come to find out that Abagail has had an affair with John Proctor (he is married to Elizabeth Proctor). This quote shows Abagail's attempt to place blame on others in regards to her affair. As the play continues, Abagail continually tries to blame others for the position she has gotten herself into. In regards to an essay topic, one could support that Abagail is not a woman who takes responsibility for her actions. Instead, she continually looks for others to blame or circumstances which she can use to take the light off of herself.

The next quote comes from Act One and is, again, spoken by Abagail:

I want to open myself! . . . I want the light of God, I want the sweet love of Jesus! I danced for the Devil; I saw him, I wrote in his book; I go back to Jesus; I kiss His hand. I saw Sarah Good with the Devil! I saw Goody Osburn with the Devil! I saw Bridget Bishop with the Devil!

Here readers can see that Abagail's confession is not one in which she gives in honesty. Instead, her confession is given so that she can be freed from persecution. (According to Salem law, if one confesses to consorting with the Devil they are considered innocent and redeemed. As seen in the previous quote, Abagail is simply concerned with her own welfare and worries about no one but herself. She gives up the name sof others so that the officials can move their concern away from her and they can charge others with witchcraft.

The last quote is given by John Proctor at the end of the play:

Because it is my name! Because I cannot have another in my life! Because I lie and sign myself to lies! Because I am not worth the dust on the feet of them that hang! How may I live without my name? I have given you my soul; leave me my name!

John has admitted to the affair with Abagail. He is now charged with signing his name to a paper which will be posted for all of the town to see. He knows that signing the paper will save his life, he has already admitted to the affair, but he does not understand why the verbal admittance is enough. He states that everything else has been taken from him- he is no longer the respected man that he was before. He refuses to sign his name to the paper because it is the only thing that he has left that is truly his.

In regards to an essay about the above quote, one could examine the lengths one would go to to save something which means more to them than all else. We are given a name- it is the one thing that no one should be able to take from us.