Verily, We took the covenant of the Children of Israel and sent Messengers to them. Whenever there came to them a Messenger with what they themselves desired not, a group of them they called liars, and others among them they killed (70)They thought there will be no Fitnah (trial or punishment), so they became blind and deaf; after that Allah turned to them (with forgiveness); yet again many of them became blind and deaf. And Allah is the All-Seer of what they do (71)
Allah reminds that He took the covenant and pledges from the Children of Israel to hear and obey Him and His Messenger. They broke these pledges and covenants and followed their lusts and desires instead of the law, and whichever part of the law they agreed with, they took it. Otherwise, they abandoned it, if it did not conform to their desires. This is why Allah said,
كُلَّمَا جَاءَهُمْ رَسُولٌ بِمَا لَا تَهْوَىٰ أَنفُسُهُمْ فَرِيقًا كَذَّبُوا وَفَرِيقًا يَقْتُلُونَ - وَحَسِبُوا أَلَّا تَكُونَ فِتْنَةٌ فَعَمُوا وَصَمُّوا
(Whenever there came to them a Messenger with what they themselves desired not - a group of them they called liars, and others among them they killed. They thought there will be no Fitnah (trial or punishment) so they became blind and deaf.)
thinking that they would suffer no repercussions for of the evil that they committed. Consequently, they were blinded from the truth and became deaf, incapable of hearing the truth. For these reasons they were unable to be guided by it. Allah forgave that, then,
عَمُوا وَصَمُّوا
(yet they became blind and deaf) again,
كَثِيرٌ مِّنْهُمْ وَاللَّهُ بَصِيرٌ بِمَا يَعْمَلُونَ
(many of them, and Allah is the All-Seer of what they do.) He has perfect knowledge of what they do and whomever among them deserves the guidance and whomever deserves misguidance.