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فَبِمَا نَقْضِهِم مِّيثَاقَهُمْ وَكُفْرِهِم بَآيَاتِ ٱللَّهِ وَقَتْلِهِمُ ٱلأَنْبِيَآءَ بِغَيْرِ حَقٍّ وَقَوْلِهِمْ قُلُوبُنَا غُلْفٌ بَلْ طَبَعَ ٱللَّهُ عَلَيْهَا بِكُفْرِهِمْ فَلاَ يُؤْمِنُونَ إِلاَّ قَلِيلاً
-An-Nisâ’ ( النساء )

Al Qushairi Tafsir

So, for their breaking their covenant and disbelieving in the signs of God, and slaying the prophets wrongfully, and for their saying, “Our hearts are covered up”-nay, but God sealed them for their disbelief; so they do not believe, except for a few.
Its meaning is: Because they committed these prohibited acts (li-irtikābihim hādhihi al-manāhī) and because they were marked by acts that deserve punishment (wa-li-ittiṣāfihim bi-hādhihi al-majāzī), We caused them to alight at the dwellings of disgrace (aḥlalnāhum manāzila al-hawān) and sent down upon them punishments of all kinds (wa-anzalnā bihim min al-ʿuqūbati funūna al-alwān).
It is said that the misfortune of their oppositional acts affected them cumulatively. One of the consequences of acting disobediently is being left to commit even more prohibited acts. By violating the covenant and not repenting, they were pulled toward disbelief in [God's] signs. Then, because of the misfortune of this disbelief, they were left to themselves until they slew the prophets (عليه السلام) wrongfully. Then, because of the misfortune of [these ever more shameful acts], they had the audacity to claim a keen ability to comprehend, saying “Our hearts are the vessels for all kinds of knowledge.” God replied to them, “but God sealed them for their dis- belief.” He hid the place of deeper knowledge (ʿirfān) from them and they wandered about in their errors.