Flower of Devotion

Venerable Mary of Jesus describes in her apparitions how the fall of the evil angels occurs:

“In the beginning the angels received a clear knowledge of the essence of God, that He is one in His essence and threefold in Persons. At the same time, they were commanded to render divine homage and praise to God as their Creator and supreme Lord, who is infinite in His Essence and in His perfections. All obeyed this command, but not all equally. The good angels obeyed out of love and justice, submitting their wills to their own, accepting with faith that which was beyond their powers of discernment, and joyfully obeying the commands given to them. Lucifer, on the other hand, surrendered because it seemed impossible to him to do the opposite. His submission was not out of perfect love, for he was dividing his will among himself and the sure truth of God. This was because he found the commandment heavy and uncomfortable, and that he was not doing it out of full love and justice, and that he had put himself in a position that led him to disobedience.
In the second place, God revealed to the angels that He wished to create human nature, i.e., a creature endowed with inferior reason, so that they too might love and worship God as their Creator and as their eternal Good, and that they might fear Him. He also declared that he would mark this human nature with great graces, that the second Person of the Most Holy Trinity would assume the same nature and unite it personally with the Divinity. Further, that the angels will have to recognize this Person, that is, this God-Man, not only in so far as He is God, but also in so far as He is a man, as their Head, and to render Him humble worship and divine homage; and that they would be inferior to him in dignity and grace and would be his servants. Then they received the command to recognize this God-Man as their Head.
All the holy and obedient angels obeyed this command, and manifested with all the strength of their wills and in humility the most complete obedience of their loving hearts. Lucifer, on the other hand, out of pride and jealousy, resisted and called upon the angels who followed him to do likewise. And so they did, united themselves with him, and refused to obey God’s command. For this the prince of darkness promised them that he should be their head, and that he would hold a separate dominion, independent of Christ.
Thus jealousy, pride, and lust caused the angel’s soul to become so blinded that it became the cause of the infection of innumerable angels with the plague of sin.