SIMON: I’m trying to put this as delicately as I can. How do I know you won’t kill me in my sleep?
MAL: You don’t know me, son, so let me explain this to you once: If I ever kill you, you’ll be awake, you’ll be facing me, and you’ll be armed.
SIMON: Are you always this sentimental?
MAL: I had a good day.

Joss Whedon (b. 1964) American screenwriter, author, producer [Joseph Hill Whedon]
Firefly, 1×01 “Serenity” (pilot) (20 Dec 2002)