(O ye who believe! Be ye staunch in justice…) [4:135].
Asbat related that al-Suddi said: “This was revealed about the Prophet, Allah bless him and give him peace. A poor man and a rich man went to him to settle a dispute. He was inclined to judge in favour of the poor man because he thought that a poor man cannot wrong a rich person. But Allah, exalted is He, wanted to establish justice regarding the poor and rich alike. He said: (O ye who believe! Be ye staunch in justice) up to His words (whether (the case be of) a rich man or a poor man, for Allah is nearer unto both (than ye are)…)”.
Asbab Al-Nuzul by Al-Wahidi , trans. Mokrane Guezzou