How Weak the Wicked Are!
See for a moment how weak the wicked are. They cannot even reach the spot to which instinct is leading and almost pushing them. What would happen if they lacked even this help from nature, so strong as to seem irresistible?
Look how impotent they are! They long for objects that are simple and of little account and yet they do not even succeed in attaining these.
They indeed lack any strength whatsoever.
Do they abandon virtue and run back to vice because they do not know what is truly good? Nothing is so weak as the blindness of ignorance.
Or perhaps they know very well what they ought to be seeking? Then it is the passions that lead them astray; it is lack of self-control that makes them too feeble to fight against vice.
Yes, they are able to do evil. But this ability comes not from any power they might have, but rather from their weakness.
Boethius The Consolations of Philosophy, 4, 2 (PL63, 793)
Sin is a Contagious Disease
Doctors speak of an epidemic when a disease is caught by just one person or animal and then infects them all. It is like that with those who commit sin. They infect one another, they are ill together and they die together.
Look at the prostitutes who camp out in the squares. They despise sensible people and they talk about their degrading exploits as if they were things to be admired. Diseased creatures, they want to spread their own evil to others. They want many others to become like themselves, because the more people there are suffering from the very same illness, the less they feel guilty of anything shameful.
When a piece of material is inflammable, it is impossible to stop it catching fire, especially if the wind is blowing.
So it is with sin. It attacks a single individual first, but then the people nearby are bound to be infected. The fascination of evil attracts many, all except the very healthy.
Basil the Great Commentary on Psalm I, 6 (PG29, 235)
~ Thomas Spidlik, Drinking from the Hidden Fountain, A Patristic Breviary: Ancient Wisdom for Today’s World