Dalil

Quran Ash-Shu'ara 26:180

وَمَآ أَسۡـَٔلُكُمۡ عَلَيۡهِ مِنۡ أَجۡرٍۖ إِنۡ أَجۡرِيَ إِلَّا عَلَىٰ رَبِّ ٱلۡعَٰلَمِينَ

Translation

And I do not ask you for it any payment. My payment is only from the Lord of the worlds.