Narrated Buraydah ibn al-Hasib:
The Prophet (peace be upon him) said: Judges are of three types, one of whom will go to Paradise and two to Hell. The one who will go to Paradise is a man who knows what is wright and gives judgement accordingly; but a man who knows what is right and acts tyranically in his judgement will go to Hell; and a man who gives judgement for people when he is ignorant will go to Hell.
[Abu Dawud Book 24, Hadith 3566]
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