Thomas Aquinas, on Job 38:19

“Where is the way where light dwelleth, and where is the place of darkness:”

“When he has said these things about the action of heavenly light on lower bodies, he mentions the light itself when he says, "Tell me, if you know everything," so that you are fit to argue with God who knows everything, "in which path does light dwell?" Consider here that light is found in the heavenly bodies of the world, which are called luminaries because of the fact that they are vessels of light. But since a path refers to motion, the question of the path in which the light dwells refers to the motion of the luminaries. Exactly how the luminaries move exceeds human knowledge, which is shown from the different opinions of men concerning their motions. Some assert that they move by eccentric movement [not having the axis in the center] and epicycles, others by the motion of the different spheres. So just as the movement of the luminaries causes light as they move in the upper hemisphere, so also darkness proceeds from their motion as they are moved in the lower hemisphere, this also presents the same difficulty, and so he says, "and where is the place of darkness."”

Imported from an open dataset — not yet checked against the printed edition.