The Prophet [SAW] said:

The Prophet [SAW] said: "Those who are just and fair will be with Allah, Most High, on thrones of light, at the right hand of the Most Merciful, those who are just in their rulings and in their dealings with their families and those of whom they are in charge." Muhammad (one of the narrators) said in his Hadith: "And both of His hands are right hands."
Narrated from 'Abdullah bin 'Amr bin Al-'As
Sunan an-Nasa'i 
(1)Chapter: Virtue of the Judge Who is Just in Passing Judgement
49 The Book of the Etiquette of Judges
Grade : Sahih (Darussalam)
Reference : Sunan an-Nasa'i 5379
In-book reference : Book 49, Hadith 1
English translation : Vol. 6, Book 49, Hadith 5381
أَخْبَرَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ عَمْرٍو، ح وَأَنْبَأَنَا مُحَمَّدُ بْنُ آدَمَ بْنِ سُلَيْمَانَ، عَنِ ابْنِ الْمُبَارَكِ، عَنْ سُفْيَانَ بْنِ عُيَيْنَةَ، عَنْ عَمْرِو بْنِ دِينَارٍ، عَنْ عَمْرِو بْنِ أَوْسٍ، عَنْ عَبْدِ اللَّهِ بْنِ عَمْرِو بْنِ الْعَاصِ، عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " إِنَّ الْمُقْسِطِينَ عِنْدَ اللَّهِ تَعَالَى عَلَى مَنَابِرَ مِنْ نُورٍ عَلَى يَمِينِ الرَّحْمَنِ الَّذِينَ يَعْدِلُونَ فِي حُكْمِهِمْ وَأَهْلِيهِمْ وَمَا وَلُوا ". قَالَ مُحَمَّدٌ فِي حَدِيثِهِ " وَكِلْتَا يَدَيْهِ يَمِينٌ ".
(1) باب فَضْلِ الْحَاكِمِ الْعَادِلِ فِي حُكْمِهِ
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