How did Plotinus influence Augustine’s religious and philosophical thought?

Plotinus exerted a profound influence on the religious and intellectual development of St. Augustine, shaping his philosophical methods and core metaphysical convictions.12

Epistemology and Metaphysics

Augustine adopted the Neoplatonic view that a spiritual, eternal realm of Truth exists beyond the sensory world. He utilized the concept of illumination, arguing that human minds perceive necessary, immutable truths—such as those in mathematics and ethics—not through sense experience, but through the direct action of divine light upon the soul. Like Plotinus, Augustine maintained a strict mind-body dualism, asserting the soul's superiority and independence from the body.21

Theology and Ethics

Plotinian thought significantly influenced Augustine’s Trinitarian theology. Augustine sought to provide a philosophical basis for the Trinity, famously exploring analogies of the divine mystery within the internal activities of the human soul. While he adapted Platonic themes regarding the inferiority of bodily pleasures, he diverged from Plotinus by emphasizing the necessity of divine grace to overcome original sin, as well as the personal, mutable nature of the human relationship with God.13