Al-An'am - 6:111

وَلَوْ أَنَّنَا نَزَّلْنَا إِلَيْهِمُ الْمَلآئِكَةَ وَكَلَّمَهُمُ الْمَوْتَى وَحَشَرْنَا عَلَيْهِمْ كُلَّ شَيْءٍ قُبُلاً مَّا كَانُواْ لِيُؤْمِنُواْ إِلاَّ أَن يَشَاء اللّهُ وَلَـكِنَّ أَكْثَرَهُمْ يَجْهَلُونَ
[6:111]
And even if We had sent down to them the angels and the dead had spoken to them and We had brought together all things before them, they would not believe unless Allah pleases, but most of them are ignorant.
Even if We did send unto them angels, and the dead did speak unto them, and We gathered together all things before their very eyes, they are not the ones to believe, unless it is in Allah's plan. But most of them ignore (the truth).
And though We should send down the angels unto them, and the dead should speak unto them, and We should gather against them all things in array, they would not believe unless Allah so willed. Howbeit, most of them are ignorant.