“My book might be filthy, but my life is blameless.”—has a certain Victorian ring, not so? But the new issue of The “Quote, Unquote” Newsletter traces it the Latin writer Martial: Lasciva* est nobis pagina, vita proba. Wonder where Martial pinched it.
I confuse it in my mind with “His sins were scarlet, but his books were read”—not, as you might think, Dorothy Parker but (if you believe Google) Hilaire Belloc. It was a favorite of my mother's; she always did enjoy a saucy one-liner. But I think she usually said “Her sins,” etc., which sounds more appropriate, somehow.
I believe it was Dorothy Parker who wrote these “Words of Comfort to Be Scratched on a Mirror" (link):
Helen of Troy had a wandering glance;
Sappho's restriction was only the sky;
Ninon was ever the chatter of
But oh, what a good girl am I!
Source for the Martial ref: The “Quote, Unquote” Newsletter, vo. 17, No. 2, April 2008, Item A3853, p6.
*As corrected. I had written "lascivia," but I am corrected by a guy who knows an adjective from a noun (link). The error was mine, not QU.