Peter Chrysologus, on Exod 13:21

“And the Lord went before them to shew the way by day in a pillar of a cloud, and by night in a pillar of fire: that he might be the guide of their journey at both times.”

“At one time he appears all aglow in a bush. For you are cold with the perfidy of infidelity, and he wants to enkindle you with the heat of faith. At another time he glows like fire in a pillar extending toward heaven, that the darkness of your ignorance may be removed and that you can follow the way of saving knowledge through the wilderness of this world. At yet another time he is changed for you into a pillar of cloud, in order to restrain the burning ebullience of your passions.”

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