Ibn ʿAbbas said, "How can you ask the people of the Scriptures about their Books while you have Allah's Book (the Qur'an) which is the most recent of the Books revealed by Allah, and you read it in its pure undistorted form?"  

عَنْ كُتُبِهِمْ وَعِنْدَكُمْ كِتَابُ اللَّهِ أَقْرَبُ الْكُتُبِ عَهْدًا بِاللَّهِ تَقْرَءُونَهُ مَحْضًا لَمْ يُشَبْ  

ʿAbdullah bin ʿAbbas said, "O the group of Muslims! How can you ask the people of the Scriptures about anything while your Book which Allah has revealed to your Prophet contains the most recent news from Allah and is pure and not distorted? Allah has told you that the people of the Scriptures have changed some of Allah's Books and distorted it and wrote something with their own hands and said, 'This is from Allah, so as to have a minor gain for it. Won't the knowledge that has come to you stop you from asking them? No, by Allah, we have never seen a man from them asking you about that (the Book Al-Qur'an ) which has been revealed to you.  

يَا مَعْشَرَ الْمُسْلِمِينَ كَيْفَ تَسْأَلُونَ أَهْلَ الْكِتَابِ عَنْ شَىْءٍ وَكِتَابُكُمُ الَّذِي أَنْزَلَ اللَّهُ عَلَى نَبِيِّكُمْ ﷺ أَحْدَثُ الأَخْبَارِ بِاللَّهِ مَحْضًا لَمْ يُشَبْ وَقَدْ حَدَّثَكُمُ اللَّهُ أَنَّ أَهْلَ الْكِتَابِ قَدْ بَدَّلُوا مِنْ كُتُبِ اللَّهِ وَغَيَّرُوا فَكَتَبُوا بِأَيْدِيهِمْ قَالُوا هُوَ مِنْ عِنْدِ اللَّهِ لِيَشْتَرُوا بِذَلِكَ ثَمَنًا قَلِيلاً أَوَ لاَ يَنْهَاكُمْ مَا جَاءَكُمْ مِنَ الْعِلْمِ عَنْ مَسْأَلَتِهِمْ فَلاَ وَاللَّهِ مَا رَأَيْنَا رَجُلاً مِنْهُمْ يَسْأَلُكُمْ عَنِ الَّذِي أُنْزِلَ عَلَيْكُمْ