In Pagan Rome, purgatory was equally held up before the minds of men; but there, there seems to have been no hope held out to any of exemption from its pains. Therefore, Virgil, describing its different tortures, thus speaks:
"Nor can the grovelling mind,
In the dark dungeon of the limbs confined,
Assert the native skies, or own its heavenly kind.
Nor death itself can wholly wash their stains;
But long-contracted filth, even in the soul, remains
The relics of inveterate vice they wear,
And spots of sin obscene in every face appear.
For this are various penances enjoined;
And some are hung to bleach upon the wind,
Some plunged in water, others purged in fires,
Till all the dregs are drained, and all the rust expires.
All have their Manes, and those Manes bear.
The few so cleansed to these abodes repair,
And breathe in ample fields the soft Elysian air,
Then are they happy, when by length of time
The scurf is worn away of each committed crime.
No speck is left of their habitual stains,
But the pure ether of the soul remains."
http://philologos.org/__eb-ttb/sect45.htm