'And He made it a word,' meaning: there is no god but Allah, 'remaining in his progeny,' interpreted by Mujahid as: in his offspring, 'so that they might return,' meaning: so that they might return to the faith.
﴿وَجَعَلَهَا كَلِمَةً﴾ يَعْنِي: لَا إِلَه إِلَّا الله ﴿بَاقِيَةً فِي عَقِبِهِ﴾ تَفْسِير مُجَاهِد: فِي وَلَده ﴿لَعَلَّهُمْ يَرْجِعُونَ﴾ لكَي يرجِعوا إِلَى الْإِيمَان