His statement: "Alif-Lam-Mim. The revelation of the Book, there is no doubt in it, from the Lord of the worlds," meaning: there is no doubt in it that it is from the Lord of the worlds.
Muhammad said: "Tanzil" (revelation) is in the nominative case (marfu') as the predicate of an implicit subject, as if implying: "That which you are reciting is the revelation of the Book." It is also permissible for it to be in the nominative case as the subject (mubtada'), and the predicate of the subject would be "la rayba fihi" (there is no doubt in it).
قَوْلُهُ: ﴿الم تَنْزِيلُ الْكِتَابِ لَا رَيْبَ فِيهِ مِنْ رَبِّ الْعَالَمِينَ﴾ أَيْ: لَا شَكَّ فِيهِ أَنَّهُ مِنْ رَبِّ الْعَالَمِينِ.
قَالَ مُحَمَّدٌ: ﴿تَنْزِيل﴾ رَفْعٌ عَلَى خَبَرِ الِابْتِدَاءِ عَلَى إِضْمَارِ: الَّذِي تَتْلُو تَنْزِيلُ الْكِتَابِ، وَيَجُوزُ أَنْ يَكُونَ رَفْعُهُ عَلَى الِابْتِدَاءِ، وَيَكُونُ خَبْرُ الِابْتِدَاءِ ﴿لَا رَيْبَ فِيهِ﴾.
