Nicene and Post-Nicene Fathers: Series II/Volume XI/John Cassian/The Twelve Books/Book IX/Chapter 6

Chapter VI.

That no one comes to grief by a sudden fall, but is destroyed by falling through a long course of carelessness.

no one is ever driven to sin by being provoked through another&#8217;s fault, unless he has the fuel of evil stored up in his own heart. Nor should we imagine that a man has been deceived suddenly when he has looked on a woman and fallen into the abyss of shameful lust: but rather that, owing to the opportunity of looking on her, the symptoms of disease which were hidden and concealed in his inmost soul have been brought to the surface.