This project will track and explain the development of the Doctrine of Divine Immutability from early mythological and scriptural source material that seems to indicate that divine entities are changeable into metaphysical systems that demand a perfectly consistent deity. The Doctrine of Divine Immutability is a philosophical and theological postulate that has long been a staple of systematic metaphysics and theology, but its function in robust and fully formed systems is different than its function when it is first generated in Ancient Greece and Judah. Methodologically mostly primary sources are studied and compared with interpretive help from relevant secondary sources. Once the generation and evolution of this doctrine is understood, a more holistic understanding of the relationship between religion and philosophy will be evident. Additionally a more robust understanding of Middle Platonism and 1st and 2nd century Christianity and their relationship to Roman Stoicism will be achieved. Of particular importance to contemporary scholarship this work will allow us to understand the doctrine in its context and will shield us from anachronistic readings of the arguments that are bound to cause fundamental errors in scholarship.