Nintai Shinbō

To be a Ninja means to persevere over time.

忍体とは心を養い、技をはげみて末長く辛棒こそ真の忍者なり.

Nintai to wa kokoro o yashinai, waza o hagemite suenagaku shinbō koso shin no ninja nari.

To be a ninja means… to nurture the heart (the spirit). To perfect techniques. And to persevere over time: this is the true essence of the ninja.

This profound and wonderful teaching, passed down from Takamatsu sensei to his disciple Hatsumi sensei, connects body, mind, and spirit within the philosophy of the ninja. More broadly, it resonates with the principles of martial arts and personal development. Breaking down each part of the message helps to uncover the layers of meaning embedded within it.

1. 忍体とは (To be a ninja means…)

The character 忍 (nin) refers to patience, perseverance, and endurance, while 体 (tai) means body. In this context, however, it refers more to the entirety of being: body, mind, and spirit. This suggests that being a “ninja” is not limited to physical skills but encompasses holistic training that includes all aspects of the individual. The use of the term nin-tai highlights that the ninja is a manifestation of internal discipline, where mastery of the body is just one part of a much larger whole.

2. 心を養い (Nurturing the heart or spirit)

This part emphasizes that developing the heart or spirit is fundamental. In the Japanese context, 心 (kokoro) represents both heart and mind, referring to the emotional and mental essence of a person. The verb 養い (yashinai) means to cultivate or nurture, implying continuous growth and internal discipline that strengthens the spirit. A true ninja is not defined by their physical ability, but by their inner strength—their capacity to endure adversity and maintain calmness and clarity of thought in moments of crisis.

This concept of nurturing the heart aligns with traditional martial arts teachings, where the focus is not only on mastering combat techniques but also on refining character and developing internal qualities like compassion, patience, and determination.

3. 技をはげみて (Perfecting techniques)

技 (waza) refers to techniques, skills, or specific arts, in this case relating to the ninja’s abilities, whether physical, tactical, or mental. 励む (hagemu) is a verb that means to work diligently or to devote oneself earnestly to something. This phrase underscores the importance of constant practice and the refinement of skills.

The combination of spiritual nurturing with technical development reflects the vision of balance between the internal and the external: external prowess must be accompanied by inner strength. Without the development of heart and mind, techniques lack a true foundation.

4. 末長く辛棒こそ (And persevering over time…)

This is a crucial part of Takamatsu sensei’s message. 末長く (suenagaku) implies a long-term perspective, something that endures and extends throughout life. 辛棒 (shinbō) is a concept that can be translated as patience or perseverance, but more than simple patience, it suggests the ability to endure prolonged hardship with steadfastness.

Here, this kuden (oral transmission) highlights that the true path of the ninja is not a quick or momentary achievement, but one that demands lifelong dedication, facing and overcoming trials over time. This part of the text suggests that perseverance is the most important quality, as it enables a person not only to survive but to grow and evolve.

5. 真の忍者なり (This is the true essence of the Ninja)

Finally, this teaching concludes with a powerful statement: this perseverance is what defines a true ninja. It is not technical prowess or natural talent that makes an authentic ninja, but the ability to endure, learn, and grow in the face of adversity. According to this kuden, the true essence of the ninja lies in internal resilience and the capacity to remain steadfast on the path—not just in mastering external skills.

This passage reveals a deep and balanced vision of the ninja that transcends popular or superficial perceptions. Rather than focusing solely on physical or tactical abilities, it presents the ninja as someone whose true strength lies in their ability to nurture their spirit, perfect their techniques, and most importantly, persevere through life with patience and endurance. This teaching not only applies to martial arts practitioners but can also be understood as a life philosophy: the combination of inner growth, constant effort, and the ability to endure adversity is what leads to an authentic and meaningful life.