Claim. The principle of mutual righteousness is joint ethics — a society in which all people observe morality publicly and privately as a single ethical attitude — and in this ideal society religion becomes unnecessary because Christianity, Confucianism, Buddhism, and Islam each have their purposes completely realized.
Elaboration. Lee diagnoses present society (capitalist, Communist, and ex-Communist alike) as suffering total ethical collapse: morality has all but disintegrated, social crimes are rampant, and no one offers effective remedies (C. Principle of Mutual Righteousness). Mutual righteousness is the proposed solution — a society of joint ethics in which everyone freely observes morality at all times and places, regardless of position.
The more striking claim is what happens to religion in this society. Lee identifies a determinate purpose for each major religion and argues each will be fulfilled by the Second Advent: Christianity empowers individuals to maintain faith until the Messiah’s return; Confucianism empowers practice of virtue until universal brotherhood arrives; Buddhism empowers training and observance of Dharma until the Realm of the Lotus-store (Hua-yen/Kegon) is realized; Islam seeks theocracy centered on Allah’s sovereignty. The society of mutual existence, mutual prosperity, and mutual righteousness — centered on the Second Advent — is the world in which all four purposes are simultaneously realized. The Messiah’s teachings embrace the core teachings of all four; therefore “there is no further need for any religion to persist.”
The distinction Lee draws is between instruction and life. Traditional religions taught the ideal as something to be believed in and aspired to; the future society is the ideal lived out with the Messiah in reality. Religious doctrines centered on faith are transformed into and consummated as “living ethics centered on practice.” This is the move from doctrine to embodiment, from faith to ethics-in-practice.
This is an extraordinarily strong supersessionist claim — not merely that Christianity completes Judaism, but that the Unification fulfillment supersedes all four world religions simultaneously. Worth flagging: critics from each tradition will contest the purpose-summaries Lee assigns (e.g., whether “theocracy centering on Allah’s sovereignty” exhausts Islam, or whether Buddhism’s purpose is reducible to one Mahayana school’s eschatology). The claim collides directly with religious pluralism. Worth a thread once counter atomics exist on each tradition’s self-understanding.
See also. mutual-existence-joint-ownership-grounded-in-true-love, social-ethics-as-extension-of-family-ethics, messiah-revives-and-unifies-existing-religions