إِنَّهُۥ لَقَوْلُ رَسُولٍ كَرِيمٍ
Sentence structure
This nominal clause is the response to the oath. In إِنَّهُۥ the pronoun is the noun of إِنَّ, while قَوْلُ is its emphatic nominative predicate and is annexed to رَسُولٍ.
Ayah summary
This Qur’an is a message conveyed through an honoured angelic messenger.
إِنَّهُۥ — Indeed, it
Grammar: إِنَّ is an accusative and emphatic particle; attached هُ is its noun.
لَقَوْلُ — (is) surely a word
Grammar: Emphatic لَ precedes the nominative predicate قَوْلُ, which is also mudāf.
رَسُولٍۢ — (of) a Messenger
Grammar: genitive noun functioning as the genitive complement.
كَرِيمٍۢ — noble
Grammar: genitive adjective functioning as the adjective.