And [recall] when you said, "O Moses, we will never believe you until we see Allah outright"; so the thunderbolt took you while you were looking on.
The Saheeh International Quran Translation
وَإِذْ قُلْتُمْ يَٰمُوسَىٰ لَن نُّؤْمِنَ لَكَ حَتَّىٰ نَرَى ٱللَّهَ جَهْرَةً فَأَخَذَتْكُمُ ٱلصَّٰعِقَةُ وَأَنتُمْ تَنظُرُونَAnd [recall] when you said, "O Moses, we will never believe you until we see Allah outright"; so the thunderbolt took you while you were looking on.