Until the last century, it was generally agreed that Maimonides was a great defender of Judaism, and Spinoza—as an Enlightenment advocate for secularization—among its key opponents. However, a new scholarly consensus has recently emerged that the teachings of the two philosophers are in fact much closer than was previously thought. This book sets out to challenge the now predominant view of Maimonides as a protomodern forerunner to Spinoza—and to show that a chief reason to read Maimonides is in fact to gain distance from our progressively secularized worldview. Turning the focus from Spinoza's oft-analyzed Theologico-Political Treatise, the Ethics has at its heart a nuanced analysis of his theory of human nature. Viewing this work in contrast to Maimonides's Guide of the Perplexed, the book makes clear that Spinoza can no longer be thought of as the founder of modern Jewish identity, nor should Maimonides be thought of as having paved the way for a modern secular worldview. It dramatically revises our understanding of both philosophers.