Shepherd of Hermas 58:2
2 The estate is this world, and the lord of the estate is He that created all things, and set them in order, and endowed them with power; and the servant is the Son of God, and the vines are this people whom He Himself planted; 3 and the fences are the holy angels of the Lord who keep together His people; and the weeds, which are plucked up from the vineyard, are the transgressions of the servants of God; and the dainties which He sent to him from the feast are the commandments which He gave to His people through His Son; and the friends and advisers are the holy angels which were first created; and the absence of the master is the time which remaineth over until His coming."
Augustine City of God 12.15
On the City of God Against the PagansIf, then, among these many thoughts, I say that there have always been creatures for Him to be Lord of, who is always and ever has been Lord, but that these creatures have not always been the same, but succeeded one another (for we would not seem to say that any is co-eternal with the Creator, an assertion condemned equally by faith and sound reason), I must take care lest I fall into the absurd and ignorant error of maintaining that by these successions and changes mortal creatures have always existed, whereas the immortal creatures had not begun to exist until the date of our own world, when the angels were created; if at least the angels are intended by that light which was first made, or, rather, by that heaven of which it is said, In the beginning God created the heavens and the earth. The angels, at least did not exist before they were created; for if we say that they have always existed, we shall seem to make them co-eternal with the Creator.
Notes and References
"... Before Clement, and certainly one of his sources, the Shepherd of Hermas knows of a group of seven consisting of the six angel 'first created' (πρῶτοι κτισθέντες) who accompany the Son of God as their seventh ... By referring almost in the same breath to the Son and the first-created angels (Similitudes 5.2.6, 11; Similitudes 5.6.4, 7), the Shepherd suggests that, even though they are clearly subordinated to the Son of God, and accompany him as a celestial escort (e.g., Similitudes 9.12.7-8; compare Vis 3:4:1; Similitudes 5:5:3), the πρῶτοι κτισθέντες are his 'friends' and fellow-counselors (Similitudes 5.5.2-3). As noted by Daniélou (Jewish Christianity, 38), 'the Word appears as the chief of the six archangels, being himself the seventh.' ..."
Golitzen, Aledander The Angelomorphic Spirit in Early Christianity: Revelation, the Shepherd of Hermas, Clement of Alexandria (pp. 1-6) Jewish Roots of Christian Mysticism Series, 2015