وَجَعَلۡنَا مِنۢ بَيۡنِ أَيۡدِيهِمۡ سَدّٗا وَمِنۡ خَلۡفِهِمۡ سَدّٗا فَأَغۡشَيۡنَٰهُمۡ فَهُمۡ لَا يُبۡصِرُونَ ٩
And We have put before them a barrier and behind them a barrier and covered them, so they do not see.
Translation: Saheeh International (English)
Each word's meaning and sound
I placed before them a barrier to the truth and behind them another barrier. I covered their eyes from the truth so they cannot see in a manner that is of benefit to them. This happened to them after their stubborness and persistence in disbelief became apparent.
Al-Mukhtasar in interpreting the Noble Quran