“Judaism is not even a religion.” This striking line appears in Immanuel Kant’s Religion Within the Boundaries of Mere Reason, a book devoted to winnowing down the articles of Christian faith to what is strictly demanded by rational morality. Kant considered himself a sincere friend of religion, and he posed a question that reflected his Protestant background. How can human beings, conflicted by sinful inclinations and tempted by worldly comforts, become pleasing to God? His answer swept aside religious doctrines that required the submission of human reason to an authority outside itself. We can honor and please God only by following our own moral reason.
Kant set his ideas in opposition to Judaism, whose confrontation with modern European culture he would shape. Judaism entailed “absolutely no religious faith,” he alleged, because it imposed its laws without a proper regard for moral intentions, regulating behavior through the fear of punishment and the hope of reward. What then is Judaism, if not a religion? Kant claimed, with consequences he did not fully foresee, that Judaism was a body of legal statutes of a defunct political state. No longer regulating a real political community, its laws promoted the archaic ritualism, voluntary slavery, and social separatism that made Jewish life a fossil. Kant was wrong about Judaism—the Talmud evaluates moral intentions closely—but his vision of Jewish law as repugnant to human freedom was essential to his wider theological agenda.
For not all Jews are Jews—some, in fact, are Christians. Though Kant acknowledged that Christ embodied human moral perfection (Christ, it seems, was a perfect Kantian), he worried that Christianity offered too many opportunities to backslide into the faith it rightly superseded. What he called the “religion of the priests” had the same effect on Christians as the Mosaic law had on Jews. Its submission to scriptural and clerical authority, its traditions of prayer and ritual, and its veneration of exemplars of biblical piety—all of this, Kant charged, amounted to a “counterfeit worship” that encouraged a servile mindset that was nearly indistinguishable from Judaism. Religion Within the Boundaries of Mere Reason concluded with an attack on the Catholic doctrine of the Eucharist, whose celebration, he wrote, “cannot but work counter to the spirit of true religion.”
