"Then We gave you back the turn against them and reinforced you with wealth and children and made you more numerous in manpower," meaning: in number. This was done for them in the time of David, on the day of Saul.
﴿ثُمَّ رَدَدْنَا لَكُمُ الْكَرَّةَ عَلَيْهِمْ وَأَمْدَدْنَاكُمْ بِأَمْوَالٍ وَبَنِينَ وَجَعَلْنَاكُمْ أَكْثَرَ نفيرا﴾ أَيْ: عَدَدًا؛ فَفَعَلَ ذَلِكَ بِهِمْ فِي زَمَانِ دَاوُدَ يَوْمَ طَالُوتَ.
