Rengetsu, then known as Nobu, was introduced to swordplay around the age of six by her adoptive father Teruhisa, an amateur swordsman himself. After Nobu went to serve in Kameoka castle in 1798 when she was eight years old, she was drilled in the martial arts of a samurai lady: she learned how to use the naginata, the sword, the wooden staff plus other weapons, and she trained in the body arts of jujutsu. She may have even learned some ninjutsu.
Nobu became adept at the martial arts, attaining instructor level skills. When Nobu was out in the town she thrashed would-be mashers with jujutsu arm locks and throws. Word spread that, “Nobu is a great beauty, but don’t try to accost her. She will kick your ass.”
Even after the samurai lady Nobu became the nun Rengetsu, she practiced the martial arts on the side. Rengetsu taught jutusu privately to local ladies, and others report her practicing with wooden staff or sword. Priest Chiman witnessed Rengetsu jump over a three foot fence holding a wooden staff in her hands when she was in her seventies.
Rengetsu was a master of “disarming” opponents. When she caught a thief attempting to break into Jinko-in, she asked him, “Looking for something? Let me show you around.” The thief was so intimidated by the power of her presence he meekly followed her out of the temple.
Perhaps the most outstanding feature of Rengetsu’s brushwork is that there is not a single suki present. In the martial arts suki means “an opening,” “a lack of focus,” “slackness in one’s posture and confusion in one’s mind.” Rengetsu’s calligraphy is razor sharp. While Rengetsu writes in the feminine kana script, it is certainly not delicate – there is no mistaking that it is the work of a powerful woman warrior. Also, the strength required to fashion so much pottery out of rough clay and then deeply incise the wet pieces with script is remarkable for anyone, man or woman.
In this sense, Rengetsu’s brushwork and her pottery making can be considered an extension of her martial arts training.