Origen of Alexandria’s treatise on “self-determination” (De Principiis 3.1) has proven highly influential for subsequent theological and philosophical discussions of free will. There is still considerable debate about the finer points of Origen’s understanding of “self-determination” (to autexousion) and where his notion of it fits within the broader Ideengeschichte of free will. In this thesis I examine the free will treatise, but focus instead on the role of the Logos in his understanding of human freedom and moral transformation. In chapter one, I trace the historical development of the Logos concept from Heraclitus and the Stoics through Middle Platonism and the Biblical Platonists, particularly Philo and Clement of Alexandria, to provide a contextualization of Origen's doctrine. Then, on the basis of this contextualization, I argue (in chapters two and three) that Origen's Logos is not a neutral rational faculty but possesses a paraenetic quality, actively prompting moral agents toward virtuous action. By analyzing Origen's psychology of self-determination, especially his use of aphormē (“prompting”), I demonstrate how the Logos influences the moral choices of rational beings. In chapter four I articulate and motivate what I call the "problem of noetic sanctification" in Origen's theology, and in the fifth and final chapter I propose a solution to the problem on Origen’s behalf in which the Logos within each rational being provides a persistent, pre-cognitive motivation towards goodness, thereby facilitating noetic sanctification through interaction with Christ as the cosmic Logos and "light."