Augustine of Hippo

"When You went by in the desert, the earth was moved" [Psalm 68:8]. A desert were the nations, which knew not God: a desert they were, where by God Himself no law had been given, where no Prophet had dwelled, and foretold the Lord to come. "When," then, "You went by in the desert," when You were preached in the nations; "the earth was moved," to the faith earthly men were stirred up. But whence was it moved? "For the heavens dropped from the face of God." Perchance here some one calls to mind that time, when in the desert God was going over before His people, before the sons of Israel, by day in the pillar of cloud, by night in the brightness of fire; [Exodus 13:21] and determines that thus it is that "the heavens dropped from the face of God," for manna He rained upon His people: [Exodus 16:15] that the same thing also is that which follows, "Mount Sina from the face of the God of Israel," "with voluntary rain severing God to Your inheritance" [Psalm 68:9], namely, the God that on Mount Sina spoke to Moses, when He gave the Law, so that the manna is the voluntary rain, which God severed for His inheritance, that is, for His people; because them alone He so fed, not the other nations also: so that what next he says, "and it was weakened," is understood of the inheritance being itself weakened; for they murmuring, fastidiously loathed the manna, longing for victuals of flesh, and those things on which they had been accustomed to live in Egypt. [Numbers 11:5-6] ... Lastly, all those men in the desert were stricken down, nor were any of them except two found worthy to go into the land of promise. [Numbers 14:23-24] Although even if in the sons of them that inheritance be said to have been perfected, we ought more readily to hold to a spiritual sense. For all those things in a figure did happen to them; [1 Corinthians 10:11] until the day should break, and the shadows should be removed. [Song of Songs 2:17]