Religion within the Boundaries of Mere Reason

Generally, Kant believes that organized religion distorts the natural human tendency to seek out the good, to try to live in accordance with the moral law. Religious practices often suggest, misleadingly, that becoming a better person does not require a great deal of personal effort. Kant worries that adherents to organized religion will believe that they can attain salvation simply by uttering creeds and professing faith.

Kant also objects to the way religion blames human sin on the original sin of Adam and Eve. Kant thinks that humans are themselves to blame for their own sins, and that by faulting Adam and Eve humans refuse to take responsibility for their own sins. Instead of facing their guilt and resolving to become better, followers of organized religion become complacent about our own moral development. Kant objects to organized religion on the grounds that it stunts our natural predisposition to seek the good and teaches us to think that someone else is responsible for our sins.

Although Kant's moral religion (MR) shares some theories with Christianity, it is not simply Christianity seen at an angle. Although both MR and Christianity hold that human beings are naturally predisposed to engage in immoral behavior, Christianity says that we are fallen beings from the moment we are born, because of Adam and Eve's original sin. MR says that we are depraved because we freely choose to do bad things, and that we bear all of the responsibility for these choices. Both Christianity and MR think that truly moral behavior begins with mimicry, because people need good role models in order to become morally righteous. But while Christianity holds up Jesus as the human ideal that all humans after him should emulate, MR interprets Jesus not as a historical person who was actually perfect, but rather as the embodied ideal of a perfect moral being. Both Christianity and MR advocate striving for a state of moral perfection, but Christianity believes this perfection will only occur in heaven, while MR says it can occur on earth.

In general, individual agents are supposed to follow the moral law to whatever extent they can. Following the moral law means that they must consistently try to act from duty, and not merely from their own potentially immoral desires and interests. Individuals will sometimes act from duty in a way that also benefits them personally, but their actions are morally sound as long as a sense of duty motivates them. The spirit in which an action is performed, not the action itself, reveals the performer's morality.