إِنَّمَا ٱلْمُؤْمِنُونَ ٱلَّذِينَ إِذَا ذُكِرَ ٱللَّهُ وَجِلَتْ قُلُوبُهُمْ وَإِذَا تُلِيَتْ عَلَيْهِمْ ءَايَٰتُهُ زَادَتْهُمْ إِيمَٰنًا وَعَلَىٰ رَبِّهِمْ يَتَوَكَّلُونَ

This chapter was revealed after the battle of Badr (2 A.H.). In this battle the Muslims were victorious and thereafter considerable spoils of war fell to their lot. After the battle a dispute arose over the distribution of the booty. All such quarrels go against the God-fearing spirit. The fear of God develops the psychology of responsibility in man. The attention of a believer is focussed on his duties and not on his rights. Instead of looking at himself, he should look towards God. His heart softens in obedience to God and His prophet. He becomes a praying and worshipping subject of God. He derives satisfaction from giving to people and not from snatching things away from them. These qualities create in man the attitude of realism and readiness to admit the truth. The inevitable result of realism and admission of truth is that all mutual quarrels vanish and if at all quarrels emerge incidentally, a warning given once is enough to set matters right. 

— Source: Tazkirul Quran (Maulana Wahiduddin Khan) via Quran.com (8:2)