Sheldon: All I need is a healthy ovum and I can grow my own Leonard Nimoy.
Penny: Okay, all I'm giving you is the napkin, Sheldon.

Penny: Now, honey, it's okay. You don't have to get me anything in return.
Sheldon: Of course I do. The essence of the custom is that I now have to go out and purchase for you a gift of commensurate value and representing the same perceived level of friendship as that represented by the gift you've given me. It's no wonder suicide rates skyrocket this time of year.
Penny: Okay, you know what? Forget it. I'm not giving you a present.
Sheldon: No, it's too late. I see it. That elf sticker says to Sheldon. The die has been cast, the moving finger has writ, Hannibal has crossed the Alps.

Leonard: When we watch Frosty the Snowman, he roots for the sun.
Sheldon: Excuse me, but the sun is essential for all life on earth. Frosty is merely a bit of frozen, supernatural ephemera in a stolen hat. A crime, by the way, for which he is never brought to account.

Penny: Sheldon, did you have a Christmas tree?
Sheldon: Oh, yes. We had a tree, we had a manger, we had an inflatable Santa Claus with plastic reindeer on the front lawn. And to make things even more jolly, there were so many blinking lights on the house they induced neighborhood-wide seizures.

Penny: I always tear up when the Grinch's heart grows three sizes.
Sheldon: Tears seem appropriate. Enlargement of the heart muscle, or hypertrophic cardiomyopathy, is a serious disease which can lead to congestive heart failure.

Santa: All right, let me see if I've got this straight. A picture of you on my lap is a way to punish your girlfriend for making you celebrate Christmas?
Sheldon: Correct.
Santa: Santa thinks dating you might be punishment enough.
Sheldon: There's an argument for that, but I want to make sure.

Penny: Leonard, look. Sheldon's hugging me!
Leonard: It's a Saturnalia miracle.

Bernadette: Why'd you turn it off?
Sheldon: Because in the last ten minutes, Santa came to town, kissed mommy, and ran grandma over with a reindeer. I had a drunk uncle who did all those things. Nobody sings songs about him.

Sheldon: On the contrary I find the Grinch to be a relatable and engaging character. And I was really with him, right up to the point that he succumbed to social convention, returned the presents and saved Christmas.

Amy: (Talking about "It's A Wonderful Life") It's great. It's Christmas time, and Jimmy Stewart's really depressed and he's gonna jump off a bridge and kill himself.
Stuart: Don't need to see it, living it!

Leonard: Okay Sheldon, to start our quest, you need to open this little Christmas gift I got you.
Sheldon: Christmas? You know I don't enjoy Christmas.
Stuart: Why not?
Sheldon: Oh, where to begin? Trees indoors. Overuse of the words 'tis' and 'twas'. And the absurd custom of one stocking. Everybody knows that socks comes in pairs. Who uses one sock?
Howard: A pirate with a peg leg?
Sheldon: Actually, that helps, thank you.

Leonard: Merry Newtonmas everyone.

Sheldon: The second I go out of town, you throw a Christmas party without me?
Amy: Yeah, kinda.
Sheldon: That's so thoughtful. You guys are the best.

Sheldon: Svaty Vaclav is better known as Good King Wenceslas from the beloved Victorian Christmas carol.
Howard: Never heard of it. Must be the one Christmas song not written by a Jewish guy.

Sheldon: Oh, a scroll. I like scrolls. They're my third favourite system of transmitting the written word, after stone tablets and sky-writing.
You have all been summoned to join a thrilling Dungeons and Dragons adventure. Your quest begins in a secret northern village of elves who have all been massacred. I like where this is heading. Your task is to rescue their leader from a dungeon of ogres. Oh, that's a saucy twist. That leader's name: Santa Claus.
No, no, no!
Leonard: Its actually ho, ho, ho, but you'll get the hang of it.

Howard: Gather around, kids. It's time for Sheldon's beloved Christmas special.
Sheldon: In the pre-Christian era, as the winter solstice approached and the plants died, pagans brought evergreen boughs into their homes as an act of sympathetic magic, intended to guard the life essences of the plants until spring. This custom was later appropriated by Northern Europeans and eventually it becomes the so-called Christmas tree.
Howard: And that, Charlie Brown, is what boredom is all about.

Sheldon: Oh, Penny. I know you think you're being generous, but the foundation of gift-giving is reciprocity. You haven't given me a gift, you've given me an obligation.
Howard: Don't feel bad, Penny. It's a classic rookie mistake. My first Hanukkah with Sheldon, he yelled at me for eight nights.

Leonard: I grew up in a house full of crazy academics. Instead of leaving Santa milk and cookies, we had to leave him a research paper. And in the morning, you could tell he'd been there because the paper would be graded.
Sheldon: No wonder you love Christmas. That sounds amazing.
Leonard: It wasn't amazing. I got a C- four years in a row.
Sheldon: Yeah, I'm familiar with your work. C-minus was your gift.