Kur’an 18:104 — sura Al-Kahf, 104. ajet

ٱلَّذِينَ ضَلَّ سَعۡيُهُمۡ فِي ٱلۡحَيَوٰةِ ٱلدُّنۡيَا وَهُمۡ يَحۡسَبُونَ أَنَّهُمۡ يُحۡسِنُونَ صُنۡعًا

čiji će trud u životu na ovome svijetu uzaludan biti, a koji će misliti da je dobro ono što rade?

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