Surah Al-Araf, verse 143

وَلَمَّا جَآءَ مُوسَىٰ لِمِيقَـٰتِنَا وَكَلَّمَهُۥ رَبُّهُۥ قَالَ رَبِّ أَرِنِىٓ أَنظُرْ إِلَيْكَ ۚ قَالَ لَن تَرَىٰنِى وَلَـٰكِنِ ٱنظُرْ إِلَى ٱلْجَبَلِ فَإِنِ ٱسْتَقَرَّ مَكَانَهُۥ فَسَوْفَ تَرَىٰنِى ۚ فَلَمَّا تَجَلَّىٰ رَبُّهُۥ لِلْجَبَلِ جَعَلَهُۥ دَكًّا وَخَرَّ مُوسَىٰ صَعِقًا ۚ فَلَمَّآ أَفَاقَ قَالَ سُبْحَـٰنَكَ تُبْتُ إِلَيْكَ وَأَنَا۠ أَوَّلُ ٱلْمُؤْمِنِينَ ﴿١٤٣﴾

7:143 When Moses came at Our appointed time and his Lord spoke to him, he said, “My Lord, reveal Yourself to me so that I may look at You.” Allah said, “You will not be able to see Me. But look at the mountain; if it stays firm in its place, only then will you see Me.” When his Lord appeared to the mountain, it was leveled to dust and Moses fell unconscious. When he recovered, he said, “Glory be to You! I repent to You and I am the first of the believers.”