Chapter XIII.—The Fall of the Angels.
“But when, having assumed these forms, they convicted as covetous those who stole them, and p. 273 changed themselves into the nature of men, in order that, living holily, and showing the possibility of so living, they might subject the ungrateful to punishment, yet having become in all respects men, they also partook of human lust, and being brought under its subjection they fell into cohabitation with women; 1098 and being involved with them, and sunk in defilement and altogether emptied of their first power, were unable to turn back to the first purity of their proper nature, their members turned away from their fiery substance: 1099 for the fire itself, being extinguished by the weight of lust, and changed into flesh, they trode the impious path downward. For they themselves, being fettered with the bonds of flesh, were constrained and strongly bound; wherefore they have no more been able to ascend into the heavens.
[Comp. Recognitions, i. 30. The details here are not only fuller, but apparently represent a more developed speculation.—R.]273:1099
The text is somewhat obscure; but the following sentence shows this to be the meaning of it.