宮川如山の弟子の谷 狂竹が奈良の大和郡山の村田扇翁から伝授されたとされる「大和調子」を原曲とする海童道（わたずみどう）曲。「大和調子」は、紀州伊勢にあった鈴法山普済寺という虚無僧寺に伝わった曲とも云われるが定かではない。
このように、虚無僧が吹いていた「本曲」と呼ばれる尺八の独奏曲は、いつ頃に作られ、どこでどのように伝承されてきたのかが不明なものが多いが、はっきりしていることは、虚無僧尺八は、支配者層の慰みや暇つぶしではなく、中世期から江戸時代にかけて、薦僧（こもそう）と呼ばれた無宿の乞食僧や戦に負けた敗残兵等によって作られ幾世紀にもわたって吹き継がれてきた、徹底的に在野の、アウトサイダーの「音楽」であったということである。
日本の近代化・中央集権化を推し進めた明治新政府によって、虚無僧達が拠りどころとしてきた普化宗門が廃宗になり、虚無僧達の尺八の修行の場であり活動の拠点であった虚無僧寺が終焉を迎えたことは象徴的である。
飢餓と戦乱の地の底から生み出され、禅の修行として吹き継がれてきた虚無僧尺八は、近代以前に生まれた作者不詳の表現主義音楽とでも云うべき独自の完成度に到達しており、その無頼性と自由さにおいて世界最古のロックとも呼ぶべき作品群の集積である。
This is a Watazumido piece based on the Yamato-joushi, a piece that is said to have been passed down to Tani Kyochiku, a disciple of Miyagawa Nyozan, by Murata Senoh of Yamatokouriyama, Nara. It is said that Yamato-joushi was passed down to the Komuso temple of Reihozan Fusai-ji in Ise, Kishu, but this is not certain.
Many of these shakuhachi solo pieces, called “honkyoku,” played by komuso monks, are unclear as to when they were composed, where, and how they were passed down, but what is clear is that komuso shakuhachi was not a pastime or a way to kill time for the ruling class, but was a thoroughly unofficial, outsider “music” that was created and handed down for centuries from the Middle Ages to the Edo period by homeless beggar monks called “komoso” and defeated soldiers who had lost battles.
It is symbolic that the Fuke sect, on which komuso monks had relied, was abolished by the new Meiji government, which pushed for the modernization and centralization of Japan, and that the Komuso temples, which were the bases of their activities and where they practiced the shakuhachi, came to an end.
The komuso shakuhachi, which was born in the depths of a land of famine and war and has been passed down as a form of Zen training, has reached a unique level of perfection that could be called expressionist music of anonymous composers born before the modern era, and its freedom and unrulyness make it a collection of works that should be called the world’s oldest rock.
