Nahj al-Balāgha
Hadith 2189٣١٤. وَقَالَ (عليه السلام): رُدُّوا الْحَجَرَمِنْ حَيْثُ جَاءَ، فَإِنَّ الشَّرَّ لَا يَدْفَعُهُ إِلَّا الشَّرُّ.
314. Amīr al-mu’minīn, peace be upon him, said: Throw a stone in return from where one comes to you because evil can be met only with evil.