EXEGESIS -- ISAIAS.
"The Lord cometh into Egypt upon a light cloud. See what he says. The Lord cometh: the Lord and Saviour into this Egypt in which we are: into the place of darkness where Pharao is, the Lord cometh. He comes not except on a light cloud. What then is this light cloud? As it seems to me, it is holy Mary weighted with no human seed. This light cloud comes into the world, and bears with it the world's Creator. And what is said in Isaias? The Lord cometh into Egypt on a light cloud: and the idols of Egypt shall be broken in pieces. The Lord came, and the idols of Egypt were set in commotion, violently shaken, and destroyed. This cloud destroyed the Serapim in Alexandria; it was no emperor, no mortal man, but this cloud which came into Egypt."*
"Behold the Lord will ascend upon a light cloud, and will enter into Egypt. O the riches of Mary's virginity (Marianae virginitatis)! As the boiling pot+ so did she glow with fervour, and as a cloud she rained the grace of Christ on the lands. For of her was it written: Behold the Lord comes sitting on a light cloud.++ Light, verily, was she who knew not the burdens of wedlock, light in truth, she who lightened this world of the heavy debt of sins. Light was she who bore in her womb the remission of sins. For she it was that lightened John whilst yet in his mother's womb, who leapt at her voice, and, as an infant, exulted with joy, animated first with the sense of devotion, before being infused with the breath of life.
"Take then, O holy virgins, take of the spiritual rain of this cloud, therewith to cool all sensual ardour, and to bedew your inmost soul. The rain of this cloud our fathers announced would be the world's salvation. This rain they foretold would come down as those showers falling gently upon the earth,** which Jerobaal asked for and merited to obtain.|| Follow this good cloud, which generated within itself the Fountain wherewith it watered the whole world. Receive, then, of the free rain (voluntariam pluviam),***, the rain of benediction, which the Lord poured forth upon His inheritance. Take of this water, and let it not flow past you; because it is a boiling pot, let its fervour perfume you with the Eternal Spirit (quia olla est, spiritu vaporet aeterno)."
"The prophet here foretells that the Lord would come into Egypt, that is, to this afflicted world, on the Virgin. He called Mary a cloud, because she was of flesh; and light, because she was a Virgin, not weighted with the burdens of marriage. She is also the rod that blossomed into flower,||| because she was pure, and her virginity directed with a free heart to God, and she was not turned aside by distraction of worldly cares. Therefore it was that the Lord from the Cross gave her to S. John His most beloved disciple,++++ who had said to his father and to his mother: I do not know you,**** and when called by Christ, left his own father to follow the Word.|||| To such a one is the Virgin given, who knows not his own; to such a one is the Virgin given, who drinks in wisdom from the breast of Christ; to such a one is the Virgin given, who recognises not his brethren, and knows not his children.