1 We may remark, in the first place, regarding their Triacontad, that the whole of it marvellously falls to ruin on both sides, that is, both as respects defect and excess. They say that to indicate it the Lord came to be baptized at the age of thirty years. But this assertion really amounts to a manifest subversion of their entire argument. As to defect, this happens as follows: first of all, because they reckon the Propator among the other Æons. For the Father of all ought not to be counted with other productions; He who was not produced with that which was produced; He who was unbegotten with that which was born; He whom no one comprehends with that which is comprehended by Him, and who is on this account [Himself] incomprehensible; and He who is without figure with that which has a definite shape.
For inasmuch as He is superior to the rest, He ought not to be numbered with them, and that so that He who is impassible and not in error should be reckoned with an Æon subject to passion, and actually in error. For I have shown in the book which immediately precedes this, that, beginning with Bythus, they reckon up the Triacontad to Sophia, whom they describe as the erring Æon; and I have also there set forth the names of their [Æons]; but if He be not reckoned, there are no longer, on their own showing, thirty productions of Æons, but these then become only twenty-nine.
Source: Adversus haereses (New Advent)