Jakusho (c. 962 - 1034) was a monk of the Tendai sect of Japanese Buddhism and a literary man who lived in the mid-Heian period. His father was OE no Tadamitsu, who was a Sangi (councilor). His secular name was OE no Sadamoto.
He is also referred to as Mikawa no nyudo, Mikawa no hijiri, or Entsu Daishi (Daishi is literally a great master, an honorific title given by the Imperial Court.)
Excelling at writing and waka (a traditional Japanese poem of thirty-one syllables), Jakusho held various posts including Zusho no kami (chief of Zushoryo [the Bureau of Drawings and Books]) and Kokushi (provincial governor) of Mikawa Province, and eventually became Jugoi (Junior Fifth Rank).
When he went to take charge as Mikawa no kami (Governor of Mikawa Province), he divorced with his wife and took another woman with him to the appointed province. However, this woman died in the appointed province, which led him to become a priest under Jakushin (a priest who was YOSHISHIGE no Yasutane before becoming a priest) and live in Nyoirin-ji Temple, which was part of Enryaku-ji Temple, which was said to hold three thousand monks. He then studied the Tendai doctrine from Genshin (monk) and Esoteric Buddhism from Ningai in the Yokawa area of Enryaku-ji Temple.
He crossed the sea to Sung (the name of a Chinese empire), where he was appointed as a Sorokushi of Suzhou City, and he received a purple Buddhist priest stole and was granted the title of Entsu Daishi from Shinso (Sung). He also obtained from Chirei at Mt. Tendai the answers and their interpretations for Genshin's 27 questions about the Tendai sect. Although Jakusho tried to go back to Japan, he stayed in Gomon-ji Temple in Suzhou City due to a request by Choi, who was a Sanshishi. Then, without returning to Japan, he died in Hang Zhou City.
He is said to have had a son, Koki. Yoshimichi, a descendant of Sadamoto, lived in Yamamuragou in Omi Province and referred to himself as a member of the Yamamura clan.
When the woman whom Sadamoto took to the appointed province as Mikawa no kami died, he was so overwhelmed by the sorrow that he kept holding her body in bed for a while, instead of burying her. Several days later, when Sadamoto kissed her, she gave off the stench of death. Unable to stand it any longer and feeling sorry for her, Sadamoto finally buried her. Then, Sadamoto is said to have thought 'this world is difficult and painful' and had a religious awakening.
When Jakusho, now a priest, was begging for offerings in a city, he came across his former wife, who harassed him by saying, 'I have been wishing that you would be like this (being in reduced circumstances) as a punishment for deserting me, and now I am able to see it realized.'
Jakusho, on the contrary, was delighted rubbing his hands together, which is a sign of appreciation, and saying, 'this virtue would bring me busshin (mercy like Buddha).'