He walked away because he was angry that he’d been spat on. He would have killed the assassin, in that moment, out of his own personal anger, not out of his commitment to the ideal his lord represented.
Moore uses the samurai’s refusal to strike as the paradigmatic illustration of the Warrior archetype’s defining quality: loyalty to a transpersonal ideal rather than to ego affect.
, King Warrior Magician Lover: Rediscovering the Archetypes of the Mature Masculine, 1990thesis