3 And the angel of the Lord, he says, appeared to the shepherds, proclaiming joy to them: “For there is born in the house of David, a Saviour, which is Christ the Lord. Then [appeared] a multitude of the heavenly host, praising God, and saying, Glory in the highest to God, and on earth peace, to men of good will.” The falsely-called Gnostics say that these angels came from the Ogdoad, and made manifest the descent of the superior Christ. But they are again in error, when saying that the Christ and Saviour from above was not born, but that also, after the baptism of the dispensational Jesus, he, [the Christ of the Pleroma,] descended upon him as a dove.
Therefore, according to these men, the angels of the Ogdoad lied, when they said, “For unto you is born this day a Saviour, who is Christ the Lord, in the city of David.” For neither was Christ nor the Saviour born at that time, by their account; but it was he, the dispensational Jesus, who is of the framer of the world, the [Demiurge], and upon whom, after his baptism, that is, after [the lapse of] thirty years, they maintain the Saviour from above descended. But why did [the angels] add, “in the city of David,” if they did not proclaim the glad tidings of the fulfilment of God's promise made to David, that from the fruit of his body there should be an eternal King?
For the Framer [Demiurge] of the entire universe made promise to David, as David himself declares: “My help is from God, who made heaven and earth;” and again: “In His hand are the ends of the earth, and the heights of the mountains are His. For the sea is His, and He did Himself make it; and His hands founded the dry land. Come, let us worship and fall down before Him, and weep in the presence of the Lord who made us; for He is the Lord our God.” The Holy Spirit evidently thus declares by David to those hearing him, that there shall be those who despise Him who formed us, and who is God alone.
Wherefore he also uttered the foregoing words, meaning to say: See that you do not err; besides or above Him there is no other God, to whom you should rather stretch out [your hands], thus rendering us pious and grateful towards Him who made, established, and [still] nourishes us. What, then, shall happen to those who have been the authors of so much blasphemy against their Creator? This identical truth was also what the angels [proclaimed]. For when they exclaim, “Glory to God in the highest, and in earth peace,” they have glorified with these words Him who is the Creator of the highest, that is, of super-celestial things, and the Founder of everything on earth: who has sent to His own handiwork, that is, to men, the blessing of His salvation from heaven.
Wherefore he adds: “The shepherds returned, glorifying God for all which they had heard and seen, as it was told unto them.” For the Israelitish shepherds did not glorify another god, but Him who had been announced by the law and the prophets, the Maker of all things, whom also the angels glorified. But if the angels who were from the Ogdoad were accustomed to glorify any other, different from Him whom the shepherds [adored], these angels from the Ogdoad brought to them error and not truth.
Source: Adversus haereses (New Advent)