Qur'an 22:11

وَمِنَ ٱلنَّاسِ مَن يَعْبُدُ ٱللَّهَ عَلَىٰ حَرْفٍ ۖ فَإِنْ أَصَابَهُۥ خَيْرٌ ٱطْمَأَنَّ بِهِۦ ۖ وَإِنْ أَصَابَتْهُ فِتْنَةٌ ٱنقَلَبَ عَلَىٰ وَجْهِهِۦ خَسِرَ ٱلدُّنْيَا وَٱلْـَٔاخِرَةَ ۚ ذَٰلِكَ هُوَ ٱلْخُسْرَانُ ٱلْمُبِينُ

And among mankind is he who worshippeth Allah upon a narrow marge so that if good befalleth him he is content therewith, but if a trial befalleth him, he falleth away utterly. He loseth both the world and the Hereafter. That is the sheer loss.