He who has done ill and talks about it and thinks about it all the time does not cast the base thing he did out of his thoughts, and whatever he thinks, therein one is, one’s soul is wholly and utterly in what one thinks and so he dwells in baseness. He will certainly not be able to turn, for his spirit will grow coarse and his heart stubborn, and in addition to this he may be overcome by gloom. What would you? Rake the muck this way, rake the muck that way — it will always be muck. Have I sinned, or have I not sinned — what does Heaven get out of it? In the time I am brooding over it, I could be stringing pearls for the delight of Heaven. This is why it is written: “Depart from evil and do good” — turn wholly away from evil, do not dwell upon it, and do good. You have done wrong? Then counteract it by doing right.
— The Gerer Rebbi