The terms rational religion and natural religion refer to the notion of a knowledge of God and consequent worship of God given to every human being solely by virtue of his or her intellectual capacity (Reason). Its substance is identified with a general commandment of obedience to God’s will realized concretely in an obligation to lead a moral life (Ethics). The roots of this idea go back to antiquity via the natural law of the Middle Ages (Natural theology); in Christianity, it has been taken fo…