Paine introduces Part 3 by referring to Old-Testament prophecies often interpreted as predicting the coming of Jesus Christ. He denies that these prophecies had anything to do with Christ and thus denounces them as the foundation of false belief. Paine criticizes preachers who preach salvation on this basis. He concludes this brief preface by explaining that his religious writings have the same purpose as his older political writings—to free mankind from ignorance and submission to lies.

Since the Old Testament is filled with dreams that are said to be prophetic, Paine opens with a supposition about how the mind actually works. He identifies the “three great faculties of the mind” as imagination, judgment, and memory (169). He confesses that we cannot know exactly how these faculties operate, but he envisions a great watch that functions on its own and then compares these faculties to different parts of the watch. During sleep, imagination remains active, but judgment and memory are suspended in slumber, which explains the curious nature of our dreams and why we so often cannot remember them.

This speculation serves as a prelude to a critique of religions that rely upon the interpretation of dreams.