Qur'an 17:45

وَإِذَا قَرَأْتَ ٱلْقُرْءَانَ جَعَلْنَا بَيْنَكَ وَبَيْنَ ٱلَّذِينَ لَا يُؤْمِنُونَ بِٱلْـَٔاخِرَةِ حِجَابًا مَّسْتُورًا

And when thou recitest the Qur'an we place between thee and those who believe not in the Hereafter a hidden barrier;