5 But if they say that Judas in perishing was the image of her Enthymesis, neither in this way will the image bear any analogy to that truth which [by hypothesis] corresponds to it. For the Enthymesis having been separated from the Æon, and itself afterwards receiving a shape from Christ, then being made a partaker of intelligence by the Saviour, and having formed all things which are outside of the Pleroma, after the image of those which are within the Pleroma, is said at last to have been received by them into the Pleroma, and, according to [the principle of] conjunction, to have been united to that Saviour who was formed out of all.
But Judas having been once for all cast away, never returns into the number of the disciples; otherwise a different person would not have been chosen to fill his place. Besides, the Lord also declared regarding him, “Woe to the man by whom the Son of man shall be betrayed;” and, “It were better for him if he had never been born;” and he was called the “son of perdition” by Him. If, however, they say that Judas was a type of the Enthymesis, not as separated from the Æon, but of the passion entwined with her, neither in this way can the number twelve be regarded as a [fitting] type of the number three.
For in the one case Judas was cast away, and Matthias was ordained instead of him; but in the other case the Æon is said to have been in danger of dissolution and destruction, and [there are also] her Enthymesis and passion: for they markedly distinguish Enthymesis from the passion; and they represent the Æon as being restored, and Enthymesis as acquiring form, but the passion, when separated from these, as becoming matter. Since, therefore, there are thus these three, the Æon, her Enthymesis, and her passion, Judas and Matthias, being only two, cannot be the types of them.
Source: Adversus haereses (New Advent)