Designed as a textbook for use in courses on natural theology and used by Immanuel Kant as the basis for his Lectures on The Philosophical Doctrine of Religion, Johan August Eberhard’s Preparation for Natural Theology (1781) is now available in English for the first time. With a strong focus on the various intellectual debates and historically significant texts in late renaissance and early modern theology, Preparation for Natural Theology influenced the way Kant thought about practical cognition as well as moral and religious concepts. Access to Eberhard’s complete text makes it possible to distinguish where in the lectures Kant is making changes to what Eberhard has written and where he is articulating his own ideas. Identifying new unexplored lines of research, this translation provides a deeper understanding of Kant's explicitly religious doctrines and his central moral writings, such as the Groundwork of the Metaphysics of Morals and the Critique of Practical Reason. Accompanied by Kant’s previously untranslated handwritten notes on Eberhard's text as well as the Danzig transcripts of Kant’s course on rational theology, Preparation for Natural Theology features a dual English-German / German-English glossary, a concordance and an introduction situating the book in relation to 18th-century theology and philosophy. This is a significant contribution to twenty-first century Kantian studies.