يَا أَيُّهَا الَّذِينَ آمَنُوا كُونُوا قَوَّامِينَ بِالْقِسْطِ شُهَدَاءَ لِلَّهِ وَلَوْ عَلَىٰ أَنفُسِكُمْ أَوِ الْوَالِدَيْنِ وَالْأَقْرَبِينَ

In life it often happens that man is confronted with a situation where, on the one hand, lies the path of desire and self-interest, and on the other hand, lies the path of justice. Now those who are unmindful of God, those who have no conviction that God is watching them on all such occasions follow the path of their desire. They consider it an achievement to ignore the call of truth and take to the path of self-interest and worldly considerations. But those who fear God, who regard God as their guardian, have their eyes always set on truth and justice and act according to their demands. They sincerely desire that they may leave this world having done no injustice to anyone, having fully adhered to the path of truth and justice. This desire for truth and justice is so heightened in them that it becomes impossible for them to tolerate any behaviour which does not measure up to the standard of absolute justice. When confronted with wrongdoing, they dare to proclaim the demands of truth and justice, even if such a stand amounts to adversely affecting the interests of their family or goes against their own worldly considerations. They say only what justice would demand. It is also very wrong from the standpoint of justice to give influential persons their due while denying the rights of those who are weak and without influence. A true believer is one who deals justly with everyone, whether weak or powerful.

— Source: Tazkirul Quran (Maulana Wahiduddin Khan) via Quran.com (4:135)