4:105
إِنَّآ أَنزَلْنَآ إِلَيْكَ ٱلْكِتَـٰبَ بِٱلْحَقِّ لِتَحْكُمَ بَيْنَ ٱلنَّاسِ بِمَآ أَرَىٰكَ ٱللَّهُ ۚ وَلَا تَكُن لِّلْخَآئِنِينَ خَصِيمًا
innā anzalnā ilayka l-kitāba bil-ḥaqi litaḥkuma bayna l-nāsi bimā arāka l-lahu walā takun lil'khāinīna khaṣīman
We have sent down the Scripture to you [Prophet] with the truth so that you can judge between people in accordance with what God has shown you. Do not be an advocate for those who betray trust.
Surely, We have sent down to you (O Muhammad صلى الله عليه وسلم) the Book (this Qur’ân) in truth that you might judge between men by that which Allâh has shown you (i.e. has taught you through Divine Revelation), so be not a pleader for the treacherous.