Bleach Season 1 Episode 37

Motive of the Fist

While Chad continues his search for the place where Rukia is held at, he encounters the 8th squad captain, Kyouraku Shunsui, who tells him where his power of the fist is coming from, and that if he will continue any farther it will take his life. Chad then remembers the reason he came to the Soul Society and the promise he made to his grandfather about his power. He also remembers the day he met Ichigo and what they promised to each other.