কে ভাল কাজ করে।

إِنّا جَعَلنا ما عَلَى الأَرضِ زينَةً لَها لِنَبلُوَهُم أَيُّهُم أَحسَنُ عَمَلًا
That which is on earth we have made but as a glittering show for the earth, in order that We may test them – as to which of them are best in conduct. Quran 18: 9