The origin of Myoan Shakuhachi dates back to the mid-9th century. In China, the high priest Fuke (Puhua) always rang a handbell while singing the following gatha "Shidanoge":
"If attacked in the light, I will strike back in the light. If attacked in the dark, I will strike in the dark.";
"If from all quarters, I will strike as a whirlwind does. If attacked from the empty sky, I will thrash with a flail."
(transl. Genichi Tsuge)

Chohaku　(Zhang Bo)　a Buddhist layman adored Fuke's virtue and was attracted by the sound of his miraculous bell. Chohaku asked to become his disciple, but Fuke rejected his request. Chohaku then composed a piece of music by listening to the essence of the swinging bell, which subsequently became "Kyorei", one of Three Myoan Kyorei, the fundamental Fuke Shakuhachi pieces.

The arrival of Myoan Shakuhachi to Japan can be traced back to Hotto Kokushi, the founder of Kokoku-ji Temple in Yura, Wakayama. He visited China in 1249 and learned that the Cho family transmitted "Kyorei" from Chosan (Zhang Can)who was the grandson of the 16th Chohaku.
Hotto returned to Japan in 1254 accompanied by four Buddhist laymen. Hotto granted "Kyorei" to Kyochiku Zenji.
Kyochiku , while meditating all night at the Kokudo Buddhist temple on Mt. Asama, Ise Province, "realized" music which seemed to be divinely inspired. He then composed "Koku," "Mukaiji," completing the "San Kyorei"(Three Myoan Kyorei) today commonly known as the Myoan classics. Kyochiku experienced a religious transformation through the sound of the bamboo and from then on played the shakuhachi instead of ringing a wind-bell or chanting the gatha. As such he went on begging pilgrimages throughout Kinai (counties near Kyoto). As a consequence, people called him the latter-day Fuke.
After his death, Tengai Myofu, a legal descendent, built a temple in Kyoto and named it Kyoreizan Myoan-ji. Regarding the playing of shakuhachi as a meditative practice, Kyochiku transmitted his Zen understanding by blowing a bamboo flute instead of chanting sutras.

Source ～　https://myouan-doushukai.org/en　～