Kapu divided the world into what was noa, common and open to ordinary use, and what was kapu, set apart and restricted to some people or forbidden to everyone outside a particular time or place. The system reached deep into daily life. Certain foods, pork, bananas, coconuts and particular fish among them, were kapu to women regardless of rank, so men and women ate separately and from different provision. Commoners could not let their shadow fall across a high chief, and specific ground, heiau, the temple platforms, chiefly residences and burial places, was kapu to those without the standing or the ritual purity to enter it. Certain periods, tied to the lunar calendar and to the Makahiki season sacred to Lono, imposed kapu on activities like fishing or warfare across the whole community rather than on particular people.
Enforcement was severe by design: breaking a kapu could carry the death penalty, and the certainty of consequence, more than any single rule, was what gave the system its force. Beckwith's collection of Hawaiian tradition situates kapu as the framework the akua, the chiefs and ordinary daily conduct were all held within, rather than as a separate department of religious life alongside them.