Al-Imām ibn Kathīr quotes and says in his Tafsīr of the Qurān:
وَإِذۡ أَخَذَ ٱللَّهُ مِيثَـٰقَ ٱلَّذِينَ أُوتُواْ ٱلۡكِتَـٰبَ لَتُبَيِّنُنَّهُ ۥ لِلنَّاسِ وَلَا تَكۡتُمُونَهُ ۥ فَنَبَذُوهُ وَرَآءَ ظُهُورِهِمۡ وَٱشۡتَرَوۡاْ بِهِۦ ثَمَنً۬ا قَلِيلاً۬ۖ فَبِئۡسَ مَا يَشۡتَرُونَ (١٨٧)
(And remember) when Allāh took a covenant from those who were given the Scripture (Jews and Christians) to make it (the news of the coming of Prophet Muhammad (sallallāhu alaihi wa salam) and the religious knowledge) known and clear to mankind, and not to hide it, but they threw it away behind their backs, and purchased with it some miserable gain! And indeed worst is that which they bought. ((Aali Imrān:187)
إِنَّ ٱلَّذِينَ يَشۡتَرُونَ بِعَهۡدِ ٱللَّهِ وَأَيۡمَـٰنِہِمۡ ثَمَنً۬ا قَلِيلاً أُوْلَـٰٓٮِٕكَ لَا خَلَـٰقَ لَهُمۡ فِى ٱلۡأَخِرَةِ وَلَا يُڪَلِّمُهُمُ ٱللَّهُ وَلَا يَنظُرُ إِلَيۡہِمۡ يَوۡمَ ٱلۡقِيَـٰمَةِ وَلَا يُزَڪِّيهِمۡ وَلَهُمۡ عَذَابٌ أَلِيمٌ۬ (٧٧)
Verily, those who purchase a small gain at the cost of Allāh’s Covenant and their oaths, they shall have no portion in the Hereafter (Paradise). Neither will Allāh speak to them, nor look at them on the Day of Resurrection, nor will He purify them, and they shall have a painful torment. (Aali Imrān: 77)
Allah has censured the People of the Book (Jews and Christians) due to their turning away and abandoning their revealed books; likewise they have been censured for devoting themselves (primarily) to (attaining the pleasures of) the worldly life and preoccupying themselves with other than what they have been commanded with – following the revelation (which was revealed to them).
So upon us, oh Muslims, is to refrain from those (aforementioned) affairs which caused Allāh to censure the People of the Book.
We should fulfil that which we have been commanded with. We should (pay attention and give concern to) studying the Book of Allāh, (which was revealed to us) teach it, understand it and teach its understanding (to others), Allāh said:
أَلَمْ يَأْنِ لِلَّذِينَ آمَنُوا أَن تَخْشَعَ قُلُوبُهُمْ لِذِكْرِ اللَّهِ وَمَا نَزَلَ مِنَ الْحَقِّ وَلَا يَكُونُوا كَالَّذِينَ أُوتُوا الْكِتَابَ مِن قَبْلُ فَطَالَ عَلَيْهِمُ الْأَمَدُ فَقَسَتْ قُلُوبُهُمْ وَكَثِيرٌ مِّنْهُمْ فَاسِقُونَ. (الحديد:١٦)
Has not the time come for the hearts of those who believe (in the Oneness of Allāh – Islamic Monotheism) to be affected by Allāh’s Reminder (this Quran), and that which has been revealed of the truth, lest they become as those who received the Scripture [the Taurat (Torah) and the Injīl (Gospel)] before (i.e. Jews and Christians), and the term was prolonged for them and so their hearts were hardened? And many of them were Fāsiqun (rebellious, disobedient to Allāh). [Al-Hadīd:16]
Tafsīr al-Qurān al-‘Adheem lil Imām ibn Kathīr Vol.1 pg 5