Refutation of polytheist demands for miracles as proof

قُل لَّآ أَمْلِكُ لِنَفْسِى نَفْعًا وَلَا ضَرًّا إِلَّا مَا شَآءَ ٱللَّهُ ۚ وَلَوْ كُنتُ أَعْلَمُ ٱلْغَيْبَ لَٱسْتَكْثَرْتُ مِنَ ٱلْخَيْرِ وَمَا مَسَّنِىَ ٱلسُّوٓءُ ۚ إِنْ أَنَا۠ إِلَّا نَذِيرٌ وَبَشِيرٌ لِّقَوْمٍ يُؤْمِنُونَ

Say, "I hold not for myself [the power of] benefit or harm, except what Allāh has willed. And if I knew the unseen, I could have acquired much wealth, and no harm would have touched me. I am not except a warner and a bringer of good tidings to a people who believe."