Chapter
2 - Surah Al-Baqarah (The Cow)
Ayahs 84-86

Translation:
And when We made a covenant with you We said: ‘You shall not shed your kinsmen’s blood or turn them out of their dwellings. To this you consented and bore witness. Yet there you were, slaying your own kinsfolk, and turning a number of them out of their dwellings, and helping each other against them with sin and aggression. Though had they come to you as captives, you would have ransomed them. Surely their expulsion was unlawful. Do you then believe in one part of the Scriptures and deny another? Those of you that act thus shall be rewarded with disgrace in this world and with the most grievous punishment (on the Day of Resurrection). God is watching over all your actions. Such are they who buy the life of this world at the price of the life to come. Their punishment shall not be lightened, nor shall they be helped.
Tafsir (Commentary):
Before the advent of Islam, three Jewish tribes inhabited the area around Medina: Banu Nadheer, Banu
Quraiza, and Banu Qainqa’a. Despite the fact that all of them adhered to Mosaic law, ignorant prejudices had divided them into two groups. They had become
enmeshed, along with the polytheist tribes of Medina—Aus and Khazraj—in political manoeuvering. Banu Nadhir and Banu Quraiza had aligned themselves with the
Aus tribe, and the Banu Qainqa’a with the Khazraj. Split into separate camps in this manner, the three Jewish tribes were constantly at war with one
another. In the Battle of Bua’ath, for instance, which occurred five years before the Prophet’s emigration to Medina, Jew had fought Jew alongside their
rival Arab allies, killing their co-religionists and expelling them from their homes. Then, when hostilities ceased, they used to appeal for funds to ransom
their brethren who had been taken captive by the pagan Arabs. Such action, they would say, had been laid down in the Torah. They were willing to break God’s
commandments in regard to the life and property of other Jews. Then they would adopt a humanitarian posture on behalf of the victims of their own cruelty,
all the while seeking to clothe their self-interested politics in a cloak of piety.
This is just like killing someone unjustly, and then giving him a religious funeral. Piety does not merely consist of performing such rituals: it consists of forsaking pagan ways, suppressing one’s selfish desires, controlling one’s politics in the interest of one’s religion. This is the essence of true piety, but people do not like to involve themselves in such arduous practices. They prefer to put on a pretence of piety by conducting superficial rituals. This is tantamount to issuing a self-made edition of divine religion; it is to disregard the eternal aspect of religion and attach importance to the worldly aspect, in the hope that zeal in performing actions which hold promise of worldly fame will qualify them for the reward of true piety. But such brazen distortion of religion can only earn one God’s punishment; it does not entitle one to any reward.