The Book of the Etiquette of Judges
49/32. Chapter:
Prohibition of Passing Two Judgments on One Issue
Sunan an-Nasai
أَخْبَرَنَا الْحُسَيْنُ بْنُ مَنْصُورِ بْنِ جَعْفَرٍ، قَالَ حَدَّثَنَا مُبَشِّرُ بْنُ عَبْدِ اللَّهِ، قَالَ حَدَّثَنَا سُفْيَانُ بْنُ حُسَيْنٍ، عَنْ جَعْفَرِ بْنِ إِيَاسٍ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ أَبِي بَكْرَةَ، - وَكَانَ عَامِلاً عَلَى سِجِسْتَانَ - قَالَ كَتَبَ إِلَىَّ أَبُو بَكْرَةَ يَقُولُ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ " لاَ يَقْضِيَنَّ أَحَدٌ فِي قَضَاءٍ بِقَضَاءَيْنِ وَلاَ يَقْضِي أَحَدٌ بَيْنَ خَصْمَيْنِ وَهُوَ غَضْبَانُ " .
It was narrated that 'Abdullah bin Abi Bakrah, who was a governor in Sijistan, said: "Abu Bakrah wrote to me, saying: 'I heard the Messenger of Allah [SAW] say: No one should pass two judgments on one issue, and no one should pass judgment between two disputing parties while he is angry.'"
Reference : Sunan an-Nasa'i 5421In-book reference : Book 49, Hadith 43English translation : Vol. 6, Book 49, Hadith 5423