This is said against Valentinus, who taught that Christ took nothing of the Virgin Mary, but passed through her as through a channel or pipe.
Wherefore it pleased Him to take flesh of the womb of a woman, is known in His own secret counsels; whether that He might confer honour on both sexes alike, by taking the form of a man, and being born of a woman, or from some other reason which I would not hastily pronounce on.
Reproduced in full. Translation: Oxford 1841 (Newman), public domain (Public domain).
Also cites: De Haeres, ii