Chinese Buddhist canon
While still young, Nan left his military career so that he could commit himself fully to his study of Buddhism and to meditation. In 1942 at age 24, he went on a three-year meditation retreat in the Emei Mountains. It is said that it was there that he verified his experiences against the Chinese Buddhist canon. During this time, Nan's primary teacher was Yuan Huanxian (袁煥仙; 1887 – 1966).