What was Shepherd Book's monastery joke about?

In Firefly Ep. 8: Out of Gas, Wash walks into the dining room in the middle of Shepherd Book telling a story about his life at the monastery:

ZOE: That is not true! No.

BOOK: I swear it is.

INARA: Surely one of you must have told him.

BOOK: No! Not one of the brethren had the heart to say anything. He was so proud.

WASH: [walking into the room] Of what? What was he proud of? Who he?

BOOK: Looked rather natty, truth be told, you know.

WASH: What was natty? I wanna hear about the natty thing.

KAYLEE: Shepherd Book was just tellin' us funny stories about his life at the monastery.

WASH: Monastic humor. I miss out on all the fun.

They never explain what's so funny! I sympathize with Wash, feeling left out while everyone else is laughing.

Is the story ever explained anywhere? Writer interviews? DVD commentary?

dialogue firefly

Best Answer

We never know.

The point of the scene (according to the DVD commentary) was to introduce the characters to the audience who had not seen the pilot.

Consequently, the writers thought it a good idea to have the scene told, effectively, from Wash's point of view just like the audience.

...and he (Wash) wants to know what's so funny, and he actually never gets to hear it, and whatever you imagine was just said before you came into this scene if funnier than I could have come up with.

^{DVD Commentary by Tim Minnear (producer) and David Solomon (director)}