How did Aquinas adapt Aristotle’s idea of an unmoved mover to Christian belief in God?

St. Thomas Aquinas adapted Aristotle’s concept of the prime mover by integrating it into a broader theological framework that identified this philosophical necessity with the God of Christianity.12

While Aristotle observed that everything in motion must be moved by another, leading to the logical requirement of a first mover that is itself unmoved, Aquinas utilized this as the first of his Five Ways to demonstrate God's existence. Aquinas did not merely adopt the Aristotelian model; he transformed it by grounding it in a distinct understanding of being.12

For Aquinas, the primary mover is not just a philosophical abstraction but the personal God of Judaism and Christianity. He argued that while finite beings are dependent on external causes for their existence and activity, they ultimately point toward an unconditioned, necessary being. Unlike creatures, whose essence is distinct from their existence, Aquinas defined God as "pure being"—the act of existing itself—thereby reconciling Aristotelian logic with the Christian doctrine of a Creator who sustains the universe.23