This, then, so far as concerns us, is the reason for the angelic name in Scripture.
But, as I judge, it is necessary to inquire for what reason the theologians call all the heavenly essences together angels, yet, when they come to the manifestation of those supermundane orders themselves, they specifically name the angelic order as the one which, in a completing manner, terminates the divine and heavenly ranks. Above this order they arrange, in superior position, the adornments of the Archangels, and the Principalities, Powers, and Virtues, and whatever other essences the manifesting tradition of Scripture knows to be established above these.
We say, then, that throughout every sacred disposition the higher orders possess also the illuminations and powers of the lower dispositions; but the last orders do not participate in the excellences of those above them.
Therefore the theologians call even the most holy orders of the highest essences angels, for they too are manifestors of the thearchic illumination. But there is no reason to call the lowest order of the heavenly minds Principalities, or Thrones, or Seraphim; for it does not participate in the most excellent powers.
Rather, just as this lowest angelic order leads our divine high priests back to the splendors of the Divinity known to it, so also the powers of the essences before it, which are still more pure, lead it upward; and they belong to the divine order which consummates the angelic hierarchies.
Unless, indeed, someone should say this also: that all the angelic names are common, according to the subjection of all the heavenly powers to the deiform and God-given light, and according to their supereminent communion in it.
But in order that the account may be more exactly distinguished by us, let us reverently consider the holy and fitting properties of each heavenly disposition as they are expressed in Scripture.