He who attacks another and injures him, kindles in the other a feeling of hatred, the root of every evil. To injure another because he has injured us, even with the aim of overcoming evil, is doubling the harm for him and for oneself; it is begetting, or at least setting free and inciting, that evil spirit which we should wish to drive out.
 Leo Tolstoy, The Kingdom of God Is Within You (1894). copy citation

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Author Leo Tolstoy
Source The Kingdom of God Is Within You
Topic evil feelings
Date 1894
Language English
Reference
Note Translated by Constance Garnett
Weblink http://www.gutenberg.org/cache/epub/4602/pg4602-images.html

Context

“In the fact that it alone allows of the possibility of eradicating evil from one's own heart, and also from one's neighbor's. This doctrine forbids doing that whereby evil has endured for ages and multiplied in the world. He who attacks another and injures him, kindles in the other a feeling of hatred, the root of every evil. To injure another because he has injured us, even with the aim of overcoming evil, is doubling the harm for him and for oneself; it is begetting, or at least setting free and inciting, that evil spirit which we should wish to drive out. Satan can never be driven out by Satan. Error can never be corrected by error, and evil cannot be vanquished by evil. True non-resistance is the only real resistance to evil. It is crushing the serpent's head.” source