Avatar: The Last Airbender, Season 2

[after escaping from Azula, Aang confronts King Bumi inside a metal coffin about why he surrendered]

Aang:
I don't understand. Why didn't you free yourself? Why did you surrender when Omashu was invaded? What's the matter with you, Bumi?!

King Bumi:
[calmly] Listen to me, Aang. There are options in fighting called jing. It's a choice of how you direct your energy.

Aang:
I know! [counts with two fingers] There's positive jing when you're attacking, and negative jing when you're retreating.

King Bumi:
And neutral jing, when you do nothing!

Aang:
[suddenly surprised] There are three jings?

King Bumi:
Well, technically there are eighty-five, but let's just focus on the third. Neutral jing is the key to earthbending. It involves listening and waiting for the right moment to strike.

Aang:
That's why you surrendered, isn't it?

King Bumi:
Yes, and it's why I can't leave now. [Aang sadly turns around, feeling disappointed]

Aang:
I guess I need to find someone else to teach me earthbending.

King Bumi:
Your teacher will be someone who has mastered neutral jing. You need to find someone who waits and listens before striking. [Momo lands on Aang's shoulders]

Aang:
[happily] Hey, Momo!

King Bumi:
Momo's mastered a few jings himself! [Momo screeches loudly at Bumi] Goodbye, Aang. I'll see you when the time is right.