The critical study on gongbu(工夫) is steadily increasing. Gongbu is mainly defined as a serious practice for self-fulfillment in many religious traditions: Confucianism, Buddhism, Taoism and new relgions. But gongbu has various meanings and contexts, so it is no longer the exclusive discipline of a religion. Technically, gongbu, previously regarded as an exclusive way of practice to eastern world religions, is becoming popular and available to popular religious traditions. This paper pays attention to the case of a shaman of Jae-ryeong(載寧) who played a leading part in cheon-gi-gongbu(天機工夫), to rethink of the variety of gongbu. The cheon-gi-gongbu was deeply related to the ritual to Heaven in the mountain(山間祭天) and the belief in living Buddha(生佛信仰). Differing from the classical theory of gongbu, this was a simple, clandestine, and ingenuous way for anti-state activities. Analyzing this material, we can understand the characteristic of gongbu with confidential, rebellious, and shamanistic properties.