Martin Luther is generally considered a stark critic of Aristotle and, even more so, the medieval Aristotelianism of his age. Our article explores the development of Luther's appraisal of Aristotle's thought throughout his career with a special emphasis on the topic of theological anthropology. We will distinguish between the fundamental anthropological paradigms based on their situatedness - vertically, coram Deo, and horizontally, coram hominibus. The imago dei (Greek: Eikon tou theou) doctrine will be closely examined as Luther's essential component of his doctrine of the human being, and ethical as well as social implications will be drawn from his emphases. Aristotle's philosophical heritage will be contrasted with Luther's views on human will, conscience, sin, concupiscence, and divine grace. Our thesis is that, owing to Luther's excessive reliance on God's sovereignty and omnipotence, innate human capacities are diminished to the point of insignificance. This makes Luther's anthropology pessimistic in regards to human capacities to do good. Questions of moral responsibility, the goodness of creation (including human reason), and the meaningfulness of human moral struggles are examined in the last section of our paper. © 2021 Constantine the Philosopher University in Nitra. All rights reserved.