9:36
إِنَّ عِدَّةَ الشُّهُورِ عِنْدَ اللَّهِ اثْنَا عَشَرَ شَهْرًا فِي كِتَابِ اللَّهِ يَوْمَ خَلَقَ السَّمَاوَاتِ وَالأَرْضَ مِنْهَا أَرْبَعَةٌ حُرُمٌ ذَلِكَ الدِّينُ الْقَيِّمُ فَلا تَظْلِمُوا فِيهِنَّ أَنْفُسَكُمْ وَقَاتِلُوا الْمُشْرِكِينَ كَافَّةً كَمَا يُقَاتِلُونَكُمْ كَافَّةً وَاعْلَمُوا أَنَّ اللَّهَ مَعَ الْمُتَّقِينَ
Verily the preparations of the states which are opposed to the states above is the state in which there is a folding of two ends of society. This is in the ideal system of Allah when He first formed the human social reality. From this state, stability is untouchable. This is the deen which will esablish us and so we are not to commit oppression these states and to fight those who associate this peace and justice altogether as they fight us (i.e. at that level). And know that Allah is with the preservant.
This is a key social principle of Quran. The system of God brings both ends of society together, creating a fair distribution among the people
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