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Surah 3. Aal-Imran
Ayah 21 - 22
21إِنَّ ٱلَّذِينَ يَكْفُرُونَ بِـَٔايَـٰتِ ٱللَّهِ وَيَقْتُلُونَ ٱلنَّبِيِّـۧنَ بِغَيْرِ حَقٍّ وَيَقْتُلُونَ ٱلَّذِينَ يَأْمُرُونَ بِٱلْقِسْطِ مِنَ ٱلنَّاسِ فَبَشِّرْهُم بِعَذَابٍ أَلِيمٍ
22أُو۟لَـٰٓئِكَ ٱلَّذِينَ حَبِطَتْ أَعْمَـٰلُهُمْ فِى ٱلدُّنْيَا وَٱلْـَٔاخِرَةِ وَمَا لَهُم مِّن نَّـٰصِرِينَ
21. Verily, those who disbelieve in the Ayat of Allah and kill the Prophets without right, and kill those men who order just dealings, then announce to them a painful torment. 22. They are those whose works will be lost in this world and in the Hereafter, and they will have no helpers.
This Ayah chastises the People of the Book for the transgression and prohibitions they committed by their denials in the past and more recent times, of Allah's Ayat and the Messengers. They did this due to their defiance and rejection of the Messengers, denial of the truth and refusal to follow it. They also killed many Prophets when they conveyed to them what Allah legislated for them, without cause or criminal behavior committed by these Prophets, for they only called them to the truth,
(And kill those men who order just dealings) thus, demonstrating the worst type of arrogance. Indeed, the Prophet said,
(Kibr (arrogance) is refusing the truth and degrading people)
This is why when they rejected the truth and acted arrogantly towards the creation, Allah punished them with humiliation and disgrace in this life, and humiliating torment in the Hereafter. Allah said,
(then announce to them a painful torment) meaning, painful and humiliating,
(They are those whose works will be lost in this world and in the Hereafter, and they will have no helpers. ).