2 There are also some who maintain that he also produced Christ as his own proper son, but of an animal nature, and that mention was made of him by the prophets. This Christ passed through Mary just as water flows through a tube; and there descended upon him in the form of a dove at the time of his baptism, that Saviour who belonged to the Pleroma, and was formed by the combined efforts of all its inhabitants. In him there existed also that spiritual seed which proceeded from Achamoth.
They hold, accordingly, that our Lord, while preserving the type of the first-begotten and primary tetrad, was compounded of these four substances,— of that which is spiritual, in so far as He was from Achamoth; of that which is animal, as being from the Demiurge by a special dispensation, inasmuch as He was formed [corporeally] with unspeakable skill; and of the Saviour, as respects that dove which descended upon Him. He also continued free from all suffering, since indeed it was not possible that He should suffer who was at once incomprehensible and invisible.
And for this reason the Spirit of Christ, who had been placed within Him, was taken away when He was brought before Pilate. They maintain, further, that not even the seed which He had received from the mother [Achamoth] was subject to suffering; for it, too, was impassible, as being spiritual, and invisible even to the Demiurge himself. It follows, then, according to them, that the animal Christ, and that which had been formed mysteriously by a special dispensation, underwent suffering, that the mother might exhibit through him a type of the Christ above, namely, of him who extended himself through Stauros, and imparted to Achamoth shape, so far as substance was concerned. For they declare that all these transactions were counterparts of what took place above.
Source: Adversus haereses (New Advent)