2 But there rushed forth in advance of the rest that Æon who was much the latest of them, and was the youngest of the Duodecad which sprang from Anthropos and Ecclesia, namely Sophia, and suffered passion apart from the embrace of her consort Theletos. This passion, indeed, first arose among those who were connected with Nous and Aletheia, but passed as by contagion to this degenerate Æon, who acted under a pretence of love, but was in reality influenced by temerity, because she had not, like Nous, enjoyed communion with the perfect Father.
This passion, they say, consisted in a desire to search into the nature of the Father; for she wished, according to them, to comprehend his greatness. When she could not attain her end, inasmuch as she aimed at an impossibility, and thus became involved in an extreme agony of mind, while both on account of the vast profundity as well as the unsearchable nature of the Father, and on account of the love she bore him, she was ever stretching herself forward, there was danger lest she should at last have been absorbed by his sweetness, and resolved into his absolute essence, unless she had met with that Power which supports all things, and preserves them outside of the unspeakable greatness.
This power they term Horos; by whom, they say, she was restrained and supported; and that then, having with difficulty been brought back to herself, she was convinced that the Father is incomprehensible, and so laid aside her original design, along with that passion which had arisen within her from the overwhelming influence of her admiration.
Source: Adversus haereses (New Advent)