Kensho Furuya wrote:
The idea of being the "model" teacher is the highest form of instruction in traditional martial arts and all other traditional fine arts in Japanese culture. This concept comes from Confucianism in which the teacher or gentlemen-scholar serves as a "model" for all others to follow, imitate and esteem.
There is a fairly in-depth article written by Peter Goldsbury on this subject on this very website:
Also, Jim Vance has written a follow-up on the subject from his perspective as well: