Verse 16

قُل لَّوْ شَآءَ ٱللَّهُ مَا تَلَوْتُهُۥ عَلَيْكُمْ وَلَآ أَدْرَىٰكُم بِهِۦ فَقَدْ لَبِثْتُ فِيكُمْ عُمُرًا مِّن قَبْلِهِۦٓ أَفَلَا تَعْقِلُونَ

Say, had God willed, I would have never recited it to you and you would have never understood it, although I had indeed spent a lifetime among you prior to this. Do you not think?