On the contrary, The Master says (ii, D. 9) that "an angelic order is a multitude of heavenly spirits, who are likened to each other by some gift of grace, just as they agree also in the participation of natural gifts." Therefore the distinction of orders among the angels is not only by gifts of grace, but also by gifts of nature.
I answer that, The order of government, which is the order of a multitude under authority, is derived from its end. Now the end of the angels may be considered in two ways. First, according to the faculty of nature, so that they may know and love God by natural knowledge and love; and according to their relation to this end the orders of the angels are distinguished by natural gifts. Secondly, the end of the angelic multitude can be taken from what is above their natural powers, which consists in the vision of the Divine Essence, and in the unchangeable fruition of His goodness; to which end they can reach only by grace; and hence as regards this end, the orders in the angels are adequately distinguished by the gifts of grace, but dispositively by natural gifts, forasmuch as to the angels are given gratuitous gifts according to the capacity of their natural gifts; which is not the case with men, as above explained (Q. 62, A. 6). Hence among men the orders are distinguished according to the gratuitous gifts only, and not according to natural gifts.
From the above the replies to the objections are evident. _______________________
FIFTH ARTICLE [I, Q. 108, Art. 5]
Whether the Orders of the Angels Are Properly Named?
Objection 1: It would seem that the orders of the angels are not properly named. For all the heavenly spirits are called angels and heavenly virtues. But common names should not be appropriated to individuals. Therefore the orders of the angels and virtues are ineptly named.
Obj. 2: Further, it belongs to God alone to be Lord, according to the words, "Know ye that the Lord He is God" (Ps. 99:3). Therefore one order of the heavenly spirits is not properly called "Dominations."
Obj. 3: Further, the name "Domination" seems to imply government and likewise the names "Principalities" and "Powers." Therefore these three names do not seem to be properly applied to three orders.
Obj. 4: Further, archangels are as it were angel princes. Therefore this name ought not to be given to any other order than to the "Principalities."
Obj. 5: Further, the name "Seraphim" is derived from ardor, which pertains to charity; and the name "Cherubim" from knowledge. But charity and knowledge are gifts common to all the angels. Therefore they ought not to be names of any particular orders.