St. Gregory the Dialogist on Angelic Nature

St. Gregory the Dialogist ca. 540-604

The angelic nature is distinct from the condition of our nature, because we are both circumscribed in place and confined by blind ignorance, while the spirits of the angels, though certainly circumscribed, are nevertheless incomparably far above us in respect to their knowledge. Certainly they are more extended interiorly and exteriorly in knowing, because they contemplate the Font Itself of knowledge. For what about these things that are knowable? Do they not know them, who know Him who knows all things? Their knowledge, therefore, is very extensive in comparison to ours; nevertheless, it is very narrow in comparison to divine knowledge. In the same way, their very spirits, in comparison to our bodies, are spirit indeed; but in comparison to the Supreme and Uncircumscribed Spirit, they are body. And again, they are sent and they stand by; for, inasmuch as they are circumscribed, they go forth, and inasmuch as they are always interiorly present, they never depart. Therefore do they always see the face of the Father, while at the same time they do come to us; for they go forth to us externally by their spiritual presence, while, through internal contemplation they remain in service in the place from whence they went forth. (Moral Teaching from Job 2.3.3)

The angelic nature, when it was created, received the free choice of whether it would will to continue in humility and remain within the sight of Almighty God, or whether it would succumb to pride and fall away from beatitude… But because, though others fell, the holy angels stood firm in their beatitude, they received as a reward an absolute inability any more to fall, so that in themtheir own nature, because it can no longer be directed in any changeable way, has been solidified as if into a huge crystal. (Homilies on Ezekiel 1.7.18)

We said there are nine choirs of angels because we know on the witness of Sacred Scripture that there are Angels, Archangels, Virtues, Powers, Principalities, Dominations, Thrones, Cherubim and Seraphim. That there are Angels and Archangels almost all the pages of Sacred Scripture bear witness. The books of the Prophets, as is well-known, frequently speak of the Cherubim and Seraphim… If to the four which Paul mentions in writing to the Ephesians, that is, the Principalities, Powers, Virtues, and Dominations, we add the Thrones, there are five choirs specially designated. And if we add to these the Angels, Archangels, Cherubim and Seraphim, it will be found that there are beyond a doubt nine choirs of angels. (Homilies on the Gospels 2.34.9)