Qur'an 5:42

سَمَّـٰعُونَ لِلْكَذِبِ أَكَّـٰلُونَ لِلسُّحْتِ ۚ فَإِن جَآءُوكَ فَٱحْكُم بَيْنَهُمْ أَوْ أَعْرِضْ عَنْهُمْ ۖ وَإِن تُعْرِضْ عَنْهُمْ فَلَن يَضُرُّوكَ شَيْـًٔا ۖ وَإِنْ حَكَمْتَ فَٱحْكُم بَيْنَهُم بِٱلْقِسْطِ ۚ إِنَّ ٱللَّهَ يُحِبُّ ٱلْمُقْسِطِينَ

Listeners for the sake of falsehood! Greedy for illicit gain! If then they have recourse unto thee (Muhammad) judge between them or disclaim jurisdiction. If thou disclaimest jurisdiction, then they cannot harm thee at all. But if thou judgest, judge between them with equity. Lo! Allah loveth the equitable.