Uniqueness of the Quranic message

وَمَآ ءَاتَيْنَـٰهُم مِّن كُتُبٍ يَدْرُسُونَهَا ۖ وَمَآ أَرْسَلْنَآ إِلَيْهِمْ قَبْلَكَ مِن نَّذِيرٍ

And We had not given them any scriptures which they could study, and We had not sent to them before you, [O Muḥammad], any warner.