"And We have certainly brought them a Book which We have detailed by way of knowledge," meaning: We have clarified within it the lawful and the prohibited, the command and the prohibition, the promise and the warning, and the legal rulings.
﴿وَلَقَدْ جِئْنَاهُمْ بِكِتَابٍ فَصَّلْنَاهُ عَلَى علم﴾ يَعْنِي: بَيَّنَّا فِيهِ الْحَلَالَ وَالْحَرَامَ، وَالْأَمْرَ وَالنَّهْيَ، وَالْوَعْدَ وَالْوَعِيدَ وَالْأَحْكَامَ
