A term for Aang, a character in Avatar: The Last Airbender who is an Eastern Messiah of sorts. Being the Avatar, he is the bridge between the Spirit World and the Human World and the only hope for the salvation of humankind. He is able to manipulate all the elements using bending, which consists of magic blended with Eastern martial art styles, most notably Kung Fu.
The term was coined by GanXingba, a Youtube Artist who has created a parody series of Avatar: The Last Airbender called Avatar: The Abridged Series.
Kung Fu Action Jesus! He's fightin' the bad guys, and makin' em pay, with magic Kung Fu he'll save the day! It's Kung Fu Action Jesus!