Quran 38:86 from Surah Saad on Divine Marvels.
قُلۡ مَآ أَسۡـَٔلُكُمۡ عَلَيۡهِ مِنۡ أَجۡرٖ وَمَآ أَنَا۠ مِنَ ٱلۡمُتَكَلِّفِينَ
English translation: Say Not I ask of you for it any payment and not I am of the ones who pretend
Transliteration: qul ma asalukum alayhi min ajrin wama ana mina al-mutakalifina