Ya-Sin - 36:9

وَجَعَلْنَا مِن بَيْنِ أَيْدِيهِمْ سَدًّا وَمِنْ خَلْفِهِمْ سَدًّا فَأَغْشَيْنَاهُمْ فَهُمْ لاَ يُبْصِرُونَ
[36:9]
And We have made before them a barrier and a barrier behind them, then We have covered them over so that they do not see.
And We have put a bar in front of them and a bar behind them, and further, We have covered them up; so that they cannot see.
And We have set a bar before them and a bar behind them, and (thus) have covered them so that they see not.