A cult classic of the 80's that still gets me amped during the final fight between Bruce Leroy and Sho'Nuff, the Shogun of Harlem. The build up to Leroy's point of realization that he is the master, is what does it for me and countless fans of the adage from Buddha: we make our own path by own common sense.
The earliest film that had a similar theme I can think of off the top of my head is 1978's Circle of Iron. The hero set out on a journey to seek the meaning of life and martial arts through the writings within the book of all knowledge. When he ultimately finds it and opens it, there lies a mirror. FYI: the original idea and concept was created by Bruce Lee who had intended to star in it and be titled: The Silent Flute.
Another classic example is The Matrix. Neo's path to self actualization and triumph is only determined by accepting his nature and removing self doubt.