A [secular Jewish] Facebook friend posted the following as his status: "Commit a sin twice and it will not seem a crime. - Jewish proverb."
I am unsure about what he thinks this means, and more unsure about what it actually does mean or what its source is. Googling the phrase finds many sites listing it as a 'Jewish proverb,' but no sources are provided.
Any idea where this comes from, whether it is a 'Jewish proverb,' and what it might mean? My best guess is that it is meant to dissuade one from sinning even once because subsequent sins would be then be easier on the conscience...?