Both Iwashita Soichi (a Catholic priest) and Tsunawaki Ryumyo (a Nichiren priest) were managers of private leprosy relief institutions during the pre-wartime of the Showa era. Not only was the pre-war time of the Showa era a semi-wartime situation with overriding totalitarianism, but in the history of leprosy relief it was referred to as "the promotive period of absolute isolation." It was the heyday of the policy of total isolation for lepers, which was a long-standing negative system. This paper takes up earlier period of the Showa era from the common perspective of two persons, and the aim is to examine from the ethical side about how they undertook activities of leprosy relief. Iwashita understood that patients could get positive, independent "life" by consciously building a relationship of mutual trust with a nation state and a church through Catholicism. In the case of Tsunawaki, on the other hand, there was an unconditional acceptance of absolute relations between human beings and society called jinkyo raihai ("deep respect and honor") based on the chapter of "The Bodhisattva Never-disparaging" in the Lotus Sutra, which examined ethical problems of leprosy relief without regard to patients themselves.