Mary Cooper: When your mom gets back, I'm gonna need to apologize for the way I spoke to her.
Penny: Well, come on, she did kinda start it.
Mary Cooper: Doesn't matter. A good Christian would have turned the other cheek. On the other hand, a good Texan would have shot her, so I'll just split the difference.

Mary: He gets his temper from his daddy.
Leonard: Ah.
Mary: He's got my eyes.
Leonard: I see.
Mary: All that science stuff, that comes from Jesus.

Sheldon: Well, this is confusing for me. But I don't want to stand in the way of your happiness. So, I will condemn you internally while maintaining an outward appearance of acceptance.
Mary: That is very Christian of you.

Sheldon: I'd like you to meet Oppenheimer, Frisch, Panofsky, Feynman, Weisskopf.
Mary: Yeah, I get it. You got a lot of cats, and you gave 'em cute Jewish names.

Penny: Leonard, what time does your mom's plane get in?
Leonard: I don't know. Sometime tomorrow morning.
Penny: Don't you want to know for sure?
Leonard: No need to. As soon as she flies into California airspace, I'll feel a disturbance in the Force.

Leonard: Not once did my mother ever give me any love or affection for just being myself. I always had to earn it.
Mary Cooper: Oh, Leonard, I'm sure she loves you very much. In her own cold godless way.

Leonard: Uh, Mom, hey, tell Mary the story about how I made a Van de Graaff generator out of our vacuum cleaner.
Beverly Hofstadter: All right. He broke the vacuum cleaner.