When he said that nothing had tended so much to the knowledge of what he was, as the contemplation of the infinite perfections of God, he well knew that the best mode to attain the knowledge of God is to know one's self, as St. Augustine and St. Bernard teach us; that is to say, that in order to our obtaining peculiar lights which open to us the grandeur of God, it is necessary to be thoroughly impressed with our own vileness, be sensible of our misery, and annihilate ourselves, because the Divine Majesty only communicates itself to the humble. But St. Francis proposed to himself to explain that, when it pleases God to manifest Himself in some manner to a soul which is duly sensible of its nothingness, it is better impressed with its own nothingness, by the disproportion it sees between the Sovereign Being and His creature, which discovers to it a thousand imperfections which it was not previously aware of, as a ray of the sun penetrating into a room, discovers a multitude of atoms of which we were previously unaware. We may also form to ourselves an idea of this by our knowledge of human ignorance; an ignorant man is less sensible of his ignorance and sometimes he is not at all aware of it; he thinks he knows everything; but a very learned man knows that he is ignorant of an infinity of things, and finds his mind very confined. So also souls which are interiorly enlightened as to the greatness of the Divinity, are more perfectly aware of their own nothingness, and are more humble than those who have not similar views. The mode adopted by the former is to dive into his own nothingness by the light of faith, to humble himself continually, in order to attain to a more exalted idea of the greatness of God and to repeat frequently this prayer of St. Augustine: "O God, who art always the same! may I know myself, may I know Thee." The self-knowledge which St. Francis possessed in such perfection, prepared him sufficiently for the signal favor which God proposed to confer upon him, according to the principle of St. Augustine, that deep foundations are requisite for a building of great height. About the Festival of the Exaltation of the Cross, which is on the fourteenth of September (it is believed that it was on the eve), an angel appeared to him and gave him notice as he afterwards communicated to some of his companions, to prepare himself for all that God would do for him. "I am prepared for everything," he replied, "and I shall not in any way oppose His holy will, provided he condescends to assist me with His grace. Although I am a useless man, and unworthy that God should cast a thought on me, nevertheless, as I am His servant, I beg He may act by me, according to His good pleasure."