Verse 55

وَإِذْ قُلْتُمْ يَـٰمُوسَىٰ لَن نُّؤْمِنَ لَكَ حَتَّىٰ نَرَى ٱللَّهَ جَهْرَةً فَأَخَذَتْكُمُ ٱلصَّـٰعِقَةُ وَأَنتُمْ تَنظُرُونَ

And when you said, O Moses we will not believe you until we see God physically, then the lightning overwhelmed you as you were watching.