إِنَّ إِلَيْنَا إِيَابَهُمْ
Indeed, to Us is their return.
Fronting إِلَيْنَا highlights the destination of final return. Its religious context and the emphatic particle reinforce the force of the relation.
Grammatically, إيابهم is a verbal noun, while إلينا is a prepositional phrase. A secure rhetorical reading keeps the grammatical roles clear before explaining restriction or emphasis.