Hadith 31-122

وَبِهذَا الإِسنادِ عَنْ عَلِىِّ بْنِ أَبِي طالِبٍ‏ عَلَيْهِ السَّلامُ قالَ: وُرِثتُ عَنْ رَسُولِ اللَّهِ‏ صَلَّى اللهُ عَلَيْهِ وَآلِهِ كتابَيْنِ: كِتاب اللَّهِ وَكِتابي فِي قِرابِ سَيفي، وقِيلَ: يا أَمِيرِ الْمُؤْمِنين وَمَا الْكِتابُ الَّذِي فِي قِرابِ سَيفِكَ؟ قالَ: مَن قَتَلَ غَيْرَ قاتِلِهِ أَوْ ضَرَبَ غَيْرَ ضارِبِهِ فَعَلَيْهِ لَعْنَةُ اللَّهِ.

According to the same documentation, Ali ibn Abi Talib (a.s.) said, “I have inherited two books from God’s Prophet (S). One of them is God’s Book (the Qur’an), and the other one is the book I have put in a leather cover and hung from my sword’s scabbard.” They asked Ali (a.s.), “O Commander of the Faithful! What is the book in your sword’s scabbard?” He (a.s.) replied, “In it is written, ‘May God’s Curse be upon whoever kills anyone other than his own killer, or hits anyone other than the one who hits him.’” [36]