9 This these dainty men could not endure. They went abroad, then when they desired to return they were not received; for I had heard many things which necessitated my being cautious; I admonished them, but effected nothing. And so boiling over they began to disseminate such things as made them the miserable enticers to all vices. They utterly lost the benefit of having fasted; they lost the fruits of their temporary continence. And so now they with Satanic eagerness envy the good works of others, the fruit of which themselves have failed to keep.
Source: Letters (New Advent)