Afterwards, he became a Buddhist monk in Mutsu Province, and in Dewa Province (also called Kashima) he practiced Shugendo (mountain asceticism) and subsequently studied Ii-Zhu medicine (traditional Chinese medicine brought to Japan during the Ming dynasty) under Sanki TASHIRO, Otei, and others.
その後、陸奥国で仏門に入り、出羽国（鹿島ともいう）で修験道を学び、また田代三喜、玉鼎らより李朱医学（当時の明からもたらされた漢方医学）を修めた、信濃国・甲斐国に移り住み、国主であった戦国大名武田信虎・武田信玄父子二代の侍医となったと言われる。