Sunan an-Nasā'ī 4097✓ 3Sahih
أَخْبَرَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، قَالَ أَنْبَأَنَا الْفَضْلُ بْنُ مُوسَى، قَالَ حَدَّثَنَا مَعْمَرٌ، عَنِ ابْنِ طَاوُسٍ، عَنْ أَبِيهِ، عَنِ ابْنِ الزُّبَيْرِ، عَنْ رَسُولِ اللَّهِ صلى الله عليه وسلم قَالَ " مَنْ شَهَرَ سَيْفَهُ ثُمَّ وَضَعَهُ فَدَمُهُ هَدَرٌ " .
It was narrated from Ibn Az-Zubair that: The Messenger of Allah [SAW] said: "Whoever unsheathes his sword and starts to strike the people with it, it is permissible to shed his blood