﴿ وَإِذْ قُلْتُمْ يَٰمُوسَىٰ لَن نُّؤْمِنَ لَكَ حَتَّىٰ نَرَى ٱللَّهَ جَهْرَةًۭ فَأَخَذَتْكُمُ ٱلصَّٰعِقَةُ وَأَنتُمْ تَنظُرُونَ ﴾

“And [remember] when you said, "O Moses. indeed we shall not believe thee unto we see God face to face!" - whereupon the thunderbolt of punishment overtook you before your very eyes.”

True piety is to worship God alone, to believe in Him though one has not seen Him, to live in fear of Judgement Day, to subsist on the pure things of the earth, to prevent whomsoever one can from falling into sin. It is those who adopt this way of life who will be successful in the next world.