Surah Al-Kahf (الكهف) Ayah 104 - Tafsir | TafsirHub

ٱلَّذِينَ ضَلَّ سَعْيُهُمْ فِى ٱلْحَيَوٰةِ ٱلدُّنْيَا وَهُمْ يَحْسَبُونَ أَنَّهُمْ يُحْسِنُونَ صُنْعًا

"[They are] those whose effort is lost in worldly life, while they think that they are doing well in work.""