Only in darkness are we revealed. [...] Goodness is not goodness that seeks advantage. Good is good in the final hour, in the deepest pit, without hope, without witness, without reward. Virtue is only virtue in extremis. This is what *he* believes, and this is the reason above all I love him, my husband. My madman in a box. My Doctor.

Nardole [quoting River Song]

The Doctor: Clara? You asked me what we're going to do, I told ya. We're going to go to hell, or wherever it is people go when they die, if there is anywhere. Whatever it is we're gonna go there and we're gonna find Danny. And if it is in any way possible, we're going to bring him home. Every culture has a concept of an afterlife. I always meant to have a look around, see if I could find one.
Clara: You're going to help me?
The Doctor: Well, why wouldn't I help you?
Clara: Because of what I just did, I just...
The Doctor: You betrayed me. You betrayed our trust, you betrayed our friendship, you betrayed everything that I've ever stood for. You let me down!
Clara: Then why are you helping me?
The Doctor: Why? Do you think that I care for you so little that betraying me would make a difference?

Winning? Is that what you think it’s about? I’m not trying to win! I’m not doing this because I want to beat someone! Because I hate someone, or because I want to blame someone! It’s not because it’s fun. God knows it’s not because it’s easy! It’s not even because it works, because it hardly ever does! I do what I do because it’s RIGHT! Because it’s decent! And above all, it’s *kind*. It’s just that. Just kind.

The Doctor

And, if you really are me, with your sand shoes and your dickie bow, that calculation is still going on.

Warrior Doctor

Clara: Do you think I'm pretty?
The Doctor: No, you're too short and bossy and your nose is all funny.
Clara: Good enough.

Horse! You have failed in your mission. We are lost with no sign of Sweetville. Do you have any final words before your summary execution?

Strax

Warrior Doctor: I don't know who you are. Either of you. I haven't got the faintest idea.
Rose: They're you. They're what you become if you destroy Gallifrey. The man who regrets and the man who forgets. The moment is me. You have to decide.

Never let him see the damage. And never, ever let him see you age. He doesn't like endings.

River Song

I'm a doctor, I'm an alien from outer space, I'm a thousand years old, I have two hearts and I can't fly a plane. Can you?

The Doctor

Raggedy Man, good night.

Amy

Doctor? If Santa was only in the dream, then why was he on my roof?

Clara

The 10th Doctor: Well, loving the posh, gravelly thing. Very convincing.
The Doctor: Brave words, Dick Van Dyke.