Demon: Stick your cock up her ass, you motherfucking worthless cocksucker.
Demon: Your mother sucks cocks in Hell, Karras, you faithless slime.
Father Merrin: Especially important is the warning to avoid conversations with the demon. We may ask what is relevant but anything beyond that is dangerous. He is a liar. The demon is a liar. He will lie to confuse us. But he will also mix lies with the truth to attack us. The attack is psychological, Damien, and powerful. So don't listen to him. Remember that - do not listen.
Father Merrin: I cast you out! Unclean spirit!
Demon: Shove it up your ass, you faggot!
Father Merrin: In the Name of our Lord Jesus Christ! It is he who commands you! It is he who flung you from the gates of Heaven to the depths of Hell!
Demon: Fuck him!
Father Merrin: Be gone...
Demon: Fuck him, Karras! Fuck him!
Father Merrin: ...from this creature of God! Be gone! In the Name of the Father, the Son, and the Holy Spirit!
Burke Dennings: [to Karl] Cunting Hun! Bloody damn butchering Nazi pig!
Demon: Do you know what she did, your cunting daughter?
Regan: You're going to die up there.
[Karras sees Merrin dead on Regan's bed and gently moves him onto the floor; he beats Merrin's chest with force and checks for a heartbeat]
Father Karras: You son of a bitch!
Father Karras: Take me! Come into me! God damn you! Take me! Take me!
[the demon transfers to Karras; he is about to kill Regan but stops]
Father Karras: NOOOO!
[jumps out of the window and rolls down the stairs outside the apartment, dead]
Dr. Barringer, Clinic Director: It looks like a type of disorder that you rarely ever see any more, except in primitive cultures. We call it a somnambuliform possession. Quite frankly, we don't know much about it except that it starts with some conflict or guilt that eventually leads to the patient's delusion that his body's been invaded by an alien intelligence, a spirit if you will.
Chris MacNeil: Look, I'm telling you again and you'd better believe it: I'm not about to put her in a goddamn asylum! And I don't care what you call it! I'm not putting her away!
Dr. Barringer, Clinic Director: I'm sorry.
Chris MacNeil: You're sorry! Jesus Christ, 88 doctors and all you can tell me with all of your bullshit is...
Dr. Barringer, Clinic Director: There is one outside chance of a cure. I think of it as shock treatment. As I say, there is an outside chance...
Chris MacNeil: Will you just name it, for God's sake? What is it?
Male Doctor: Do you have any religious beliefs?
Chris MacNeil: No.
Female Doctor: What about your daughter?
Chris MacNeil: No, why?
Dr. Barringer, Clinic Director: Have you ever heard of exorcism? It's a stylized ritual in which rabbis or priests try to drive out the so-called invading spirit. It's pretty much discarded these days, except by the Catholics who keep it in the closet as a sort of embarrassment. It has worked, in fact, although not for the reason they think, of course. It was purely the force of suggestion. The victim's belief in possession helped cause it. And just in the same way, this belief in the power of exorcism can make it disappear.
[Regan, possessed, is masturbating with a crucifix]
Demon: Let Jesus fuck you, let Jesus fuck you. Let him fuck you.
Father Karras: There are no experts. You probably know as much about possession than most priests. Look, your daughter doesn't say she's a demon. She says she's the devil himself. And if you've seen as many psychotics as I have, you'd know it's like saying you're Napoleon Bonaparte.
Karras' Mother: [to Karras] Why you do this to me, Dimmy?
Chris MacNeil: [as the Ouija planchette pulls away] You really don't want me to play, huh?
Regan: No, I do. Captain Howdy said no.
Chris MacNeil: Captain who?
Regan: Captain Howdy.
Chris MacNeil: Who's Captain Howdy?
Regan: You know, I make the questions and he does the answers.
Chris MacNeil: Oh, Captain Howdy...
Demon: Your mother's in here, Karras. Would you like to leave a message? I'll see that she gets it.
Demon: Give us time... Let the girl die... I am no one... I am no one... Fear the priest... Fear the priest... Merrin... Merrin.
Subway Vagrant: Father, could you help an old altar boy? I'm Cat'lick.
Chris MacNeil: You show me Regan's double, same face, same voice, everything. And I'd know it wasn't Regan. I'd know in my gut. And I'm telling you that 'thing' upstairs isn't my daughter. Now, I want you to tell me that you know for a fact that there's nothing wrong with my daughter, except in her mind. You tell me for a fact that an exorcism wouldn't do any good. You tell me that!
Tom, President of University: [discussing the case, referring to Karras] Well, he does know the background. I doubt there's any danger in just having him assist. There should be a psychiatrist present, anyway.
Bishop Michael: What about the exorcist? Have you any ideas?
Tom, President of University: How about Lankester Merrin?
Bishop Michael: Merrin? Why, I'd a notion he was over in Iraq. I think I read he was working on a dig near Nineveh.
Tom, President of University: Yeah, you're right, Mike, but he's finished. He came back three or four months ago. He's at Woodstock now.
Bishop Michael: What's he doing there? Teaching?
Tom, President of University: No, he's working on another book.
Bishop Michael: Don't you think he's too old, Tom? How's his health?
Tom, President of University: He must be all right, he's still running around digging up tombs. Besides, he's had experience.
Bishop Michael: I didn't know that.
Tom, President of University: Ten, twelve years ago, I think, in Africa. The exorcism supposedly lasted several months. I heard it damn near killed him.
Demon: Keep away. The sow is mine.
Demon: Lick me, lick me!
Father Dyer: My idea of Heaven is a solid white nightclub with me as a headliner for all eternity, and they *love* me.
Lt. Kinderman: You go to films, Father Dyer? You like them?
Father Dyer: Oh, sure.
Lt. Kinderman: I get passes. In fact I've got a pass for the Crest tomorrow night. You'd like to go?
Father Dyer: What's playing?
Lt. Kinderman: "Wuthering Heights".
Father Dyer: Who's in it?
Lt. Kinderman: Heathcliff, Jackie Gleason, and in the role of Catherine Earnshaw, Lucille Ball. You're happy?
Father Dyer: I've seen it.
Lt. Kinderman: Another one.
Father Merrin: [looking at the Pazuzu Amulet] Evil against evil.
[last lines - original version]
Chris MacNeil: Father Dyer? I thought you'd like to keep this.
Father Karras: It's my mother, Tom. She's alone. I never should have left her. At least in New York, I'd be near, I'd be closer.
Tom, President of University: Could see about a transfer, Damien.
Father Karras: I need re-assignment, Tom. I want out of this job. It's wrong. It's no good.
Tom, President of University: You're the best we've got.
Father Karras: Am I really? It's more than psychiatry, and you know that Tom. Some of their problems come down to faith, their vocation and meaning of their lives, and I can't cut it anymore. I need out. I'm unfit. I think I've lost my faith, Tom.
Father Karras: [praying over Merrin's body] Ego te absolvo in nomine Patris, et Filiii, et Spiritus Sancti. Amen.
Lt. Kinderman: If certain British doctors never asked "What is this fungus?" we wouldn't today have penicillin, correct?
Dr. Barringer, Clinic Director: There is one outside chance for a cure. I think of it as shock treatment - as I said, it's a very outside chance... Have you ever heard of exorcism? Well, it's a stylized ritual in which the rabbi or the priest try to drive out the so-called invading spirit. It's been pretty much discarded these days except by the Catholics who keep it in the closet as a sort of an embarrassment, but uh, it has worked. In fact, although not for the reasons they think, of course. It's purely a force of suggestion. The victim's belief in possession is what helped cause it, so in that same way, a belief in the power of exorcism can make it disappear.
Chris MacNeil: You're telling me that I should take my daughter to a witch doctor? Is that it?
Father Karras: There isn't a day in my life when I haven't felt like a fraud. I mean priests, doctors, I've talked to them all. I don't know anyone who hasn't felt that.
[to a prominent senator at Chris' party]
Burke Dennings: There seems to be an alien pubic hair in my gin. Never seen it before in my life! Have you?
Karl: It wants no straps.
Lt. Kinderman: [to Chris] A draft in the fall when the house is hot is a magic carpet for germs.
Dr. Taney: Pathological states can induce abnormal strength. Accelerated motor performance. Now, for example, say a 90 pound woman sees her child pinned under the wheel of a truck. Runs out and lifts the wheels a half a foot up off the ground - you've heard the story - same thing here. Same principle, I mean.
Chris MacNeil: So what's wrong with her?
Dr. Klein: We still think the temporal lobe.
Chris MacNeil: Oh what are you talking about, for Chrissakes? Did you see her or not? She's acting like she's fucking out of her mind, psychotic, like a... split personality or...
Dr. Taney: There haven't been more than a hundred authentic cases of so-called split personality, Mrs. MacNeil. Now I know the temptation is to leap to psychiatry. But any reasonable psychiatrist would exhaust the somatic possibilities first.
Chris MacNeil: So, what's next?
Dr. Taney: A pneumoencephalogram, I would think. Pin down that lesion. It will involve another spinal.
Chris MacNeil: Oh, Christ.
Dr. Taney: What we missed in the EEG and the arteriograms could conceivably turn up there. At least, it would eliminate certain other possibilities.
Father Karras: I should have told you I wouldn't be in uniform.
Chris MacNeil: Operator, you've given me the number four times. What did you do, take an illiteracy test to get that job for Christ sake?
Boy: [in Arabic] They've found something... small pieces.
Demon: [as Father Merrin enters the house, with terrible rage] MERRIN!
[after fighting with Karl]
Burke Dennings: So, what's for dessert?
Demon: Lick me! Lick me! Lick me!
Regan: I heard... differently.
Dr. Klein: Any reasonable psychiatrist would eliminate a physical cause first.
Father Dyer: [flamboyantly playing the piano]
Muezzin: Allahu Akbar...
Burke Dennings: We're going to hang out the washing on the Siegfried Line...