Gregory the Dialogist

Then Thou scarest me with dreams, and terrifiest me through visions. But lest anyone should be at pains to make out these words after the literal sense, it is of great importance to find out in how many ways the mind is affected by images from dreams. For sometimes dreams are engendered of fulness or emptiness of the belly, sometimes of illusion, sometimes of illusion and thought combined, sometimes of revelation, while sometimes they are engendered of imagination, thought, and revelation together. …

Morals on the Book of Job, Book VIII ↗

Thomas Aquinas

These cures too could not help him, because at the time when he should have used these remedies, other impediments like terrible dreams and horrible visions were present in him which disturbed him. To express this he continues, "Then you will frighten me with dreams," which appear to one when sleeping, and me "with visions," which appear to the one awake who has lost the use of his exterior senses, "will terrify me." Images at night are usually formed by thoughts experienced during the day and so because Job thought about sad things …

Commentary on Job ↗