The Angels Are a Being of Form and Being of Essence and Existence

All finite beings, including the angels of which we have no quidditative knowledge, are composites of potency and act of essence and existence. All such beings must receive their existence at extra from outside because an infinite regress in essentially subordinated causes is impossible. Even a potential infinitude of beings which of themselves do not exist must receive their being from without,. They can receive it only from the one who is his own being, from God.