حَدَّثَنَا حُسَيْنُ بْنُ عَلِيٍّ عَنْ زَائِدَةَ عَنْ سِمَاكٍ عَنْ حَنَشٍ عَنْ عَلِيٍّ رَضِيَ اللَّهُ عَنْهُ قَالَ قَالَ لِي النَّبِيُّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ إِذَا تَقَدَّمَ إِلَيْكَ خَصْمَانِ فَلَا تَسْمَعْ كَلَامَ الْأَوَّلِ حَتَّى تَسْمَعَ كَلَامَ الْآخَرِ فَسَوْفَ تَرَى كَيْفَ تَقْضِي قَالَ فَقَالَ عَلِيٌّ رَضِيَ اللَّهُ عَنْهُ فَمَا زِلْتُ بَعْدَ ذَلِكَ قَاضِيًا
مسند امام احمد بن حنبل · Hadith 690
It was narrated that 'Ali (RA) said: The Prophet (PBUH) said to me: "When two disputants come to you, do not listen to the words of the first one until you have also listened to the words of the other, then you will know how to judge." And 'Ali (RA) said: Since then I have continued to be a good judge.
Translated by Dr. Muhammad Muhsin Khan · Reviewed by Islamic University of Madinah · Published March 2020