2 The fallacy, then, of this exposition is manifest. For when John, proclaiming one God, the Almighty, and one Jesus Christ, the Only-begotten, by whom all things were made, declares that this was the Son of God, this the Only-begotten, this the Former of all things, this the true Light who enlightens every man, this the Creator of the world, this He that came to His own, this He that became flesh and dwelt among us—these men, by a plausible kind of exposition, perverting these statements, maintain that there was another Monogenes, according to production, whom they also style Arche.
They also maintain that there was another Saviour, and another Logos, the son of Monogenes, and another Christ produced for the re-establishment of the Pleroma. Thus it is that, wresting from the truth every one of the expressions which have been cited, and taking a bad advantage of the names, they have transferred them to their own system; so that, according to them, in all these terms John makes no mention of the Lord Jesus Christ. For if he has named the Father, and Charis, and Monogenes, and Aletheia, and Logos, and Zoe, and Anthropos, and Ecclesia, according to their hypothesis, he has, by thus speaking, referred to the primary Ogdoad, in which there was as yet no Jesus, and no Christ, the teacher of John.
But that the apostle did not speak concerning their conjunctions, but concerning our Lord Jesus Christ, whom he also acknowledges as the Word of God, he himself has made evident. For, summing up his statements respecting the Word previously mentioned by him, he further declares, “And the Word was made flesh, and dwelt among us.” But, according to their hypothesis, the Word did not become flesh at all, inasmuch as He never went outside of the Pleroma, but that Saviour [became flesh] who was formed by a special dispensation [out of all the Æons], and was of later date than the Word.
Source: Adversus haereses (New Advent)