In this paper, I wish to present the first full-fledged investigation of Benedetto Varchi’s manuscript writings on psychology, which show the depth of his familiarity with philosophy and his originality as a thinker. In particular, I wish to show that Varchi was not an Averroist. Rather in the manuscript Varchi rejects Averroistic doctrines and seeks to reconcile Aristotelian psychology with the truth of religion. In so doing, Varchi appropriates Themistius’s interpretation of Aristotle through the filter of Marcantonio Zimara’s writings, which allows him to support the immortality and indivisibility of the human soul while safeguarding the doctrines of Christian faith.