It is ordained that non-believers are obstinate to the pointof belief staying beyond their comprehension, even if miracles were to happenor angels were send down to them:
”They swear by God, with their utmost oaths, that ifmiracles were to come to them, they would believe in it. Say, the miracles wereonly with God. But, how do you know? Even if it did come, they still would notbelieve.” (06: 109)
It is recorded that Prophet Mohammad (PBUH) stated thatQuran is the miracle. The sublimity of its message, the rhythm of its idiom,the appeal that it holds is indeed a miracle. Yet, the non-believers would notbelieve in the miracle of Quran, insisting on the physical exhibit of amiracle. Miracles stay in Divine Realm and Command. However, even with thephysical exhibit of a miracle, the non-believers would not believe.
The non-believers failed to appreciate the truth from thevery start, instead of reflecting on it and appreciating its veracity. Thevirtual rebellion against Divine Norms had the Almighty Allah turn their heartsand the vision:
”And We turn their hearts and their visions, as theyrefused to believe in it the first time, and We leave them blundering in theirrebellion” (06: 110)
It was the rebellious nature of non-believers that led themto lose their visionary perception; it had a multiplier effect on the blundersthey committed, one after another, leading them to abyss, where even the angelswould not be enough to make them believe:
”Even if We send down the angels to them, and the deadspoke to them, and We gathered all things before them, they still would notbelieve, unless God wills; but most of them are ignorant” (06: 111)
Dead do not speak, but even if they were made to do so byDivine Will, and even if all evidence to support the truth was displayed, thenon-believers still would not believe, unless God Wills. But in the DivinePremise, it is the willing believers who are taken on board, not the ignorantlot with their doubts and idiosyncrasies.