City of God

But with these more estimable philosophers we have no dispute in this matter. For they perceived, and in various forms abundantly expressed in their writings, that these spirits have the same source of happiness as ourselves—a certain intelligible light, which is their God, and is different from themselves, and illumines them that they may be penetrated with light, and enjoy perfect happiness in the participation of God. Plotinus, commenting on Plato, repeatedly and strongly asserts that not even the soul which they believe to be the soul of the world, derives its blessedness from any other source than we do, viz., from that Light which is distinct from it and created it, and by whose intelligible illumination it enjoys light in things intelligible.

He also compares those spiritual things to the vast and conspicuous heavenly bodies, as if God were the sun, and the soul the moon; for they suppose that the moon derives its light from the sun. That great Platonist, therefore, says that the rational soul, or rather the intellectual soul—in which class he comprehends the souls of the blessed immortals who inhabit heaven,— has no nature superior to it save God, the Creator of the world and the soul itself, and that these heavenly spirits derive their blessed life, and the light of truth from their blessed life, and the light of truth, the source as ourselves, agreeing with the gospel where we read, “There was a man sent from God whose name was John; the same came for a witness to bear witness of that Light, that through Him all might believe.

He was not that Light, but that he might bear witness of the Light. That was the true Light which lights every man that comes into the world;” a distinction which sufficiently proves that the rational or intellectual soul such as John had cannot be its own light, but needs to receive illumination from another, the true Light. This John himself avows when he delivers his witness: “We have all received of His fullness.”