Sheldon: It's recently come to my attention that everybody lies and you can't believe a thing that comes out of anyone's mouth.
Mary: I don't think everybody lies. You don't lie.
Sheldon: No, but perhaps to get by in the world it's a skill I should cultivate.
Mary: I hope you don't. I love your honesty.
Sheldon: I want to believe you.
Mary: [scoffs] You should, because I'm your mother and I would never lie to you.
Sheldon: I would never lie to you, either.
Mary: So, I guess not everybody lies.
Sheldon: I heard what you said in your prayer, and I don't think you're failing as a mother.
Mary: Thank you. I think you're a pretty great son yourself.
Sheldon: I know I'm difficult.
Mary: There is not a single thing about you I would change.
Adult Sheldon: My mom promised she would never lie to me. And she never did.
Mary: [softly to the heavens] I'm sorry.

Sheldon: Regardless, I'm not interested in making any more friends.
Mary: Oh, I don't think that's how you really feel.
Sheldon: It is. From now on, it's a hermit's life for me.
Mary: I bet, when you grow up, you will be surrounded by lots of smart, wonderful friends.
Sheldon: I can't see that happening.

Sheldon: Mom, when should I be expecting my testicles?
Woman: [turns around] What is wrong with him?
Mary: Nothing is wrong with him. Now turn around before I knock your lights out.
Sheldon: Hello.

Mary: Sheldon Lee Cooper, if you don't finish that pork chop, I swear I will chew it up and spit it in your mouth like a mama bird.
Missy: Do it, Mom. Do it.

Mary: [prays] Please watch over Missy and Sheldon and especially Georgie. And please don't let my failings as a mother get in the way of Your plans for their lives. Amen. [gasps] Hey, baby. What's wrong?
Sheldon: Is it that obvious?
Mary: Well, you are outside, where birds live.
Sheldon: True. I'll make it quick. I'm experiencing what the Germans call weltschmerz.
Mary: Uh-huh. And what do Americans call it?
Sheldon: The pain of the world.
Mary: Sounds more fun in German.
Sheldon: Most things do.

Mary: You are unbelievable. It is bad enough for you to do all this stuff, but then to drag Georgie down into your den of sin.
Meemaw: Oh, please, it's not a den of sin. Although that is a great name. Den of Sin. That would get some butts in seats. [Mary exclaims]

Pastor Jeff: Hey, Mary. Quick question. Why can I see you through my newsletter?
Mary: Oh, sorry, I had to remove one of the ads.
Pastor Jeff: Was there anything important on the other side?
Mary: Just Peg's recipe for her grape salad.
Pastor Jeff: With the mayonnaise and the pretzels. Barf.