Quran 39:41 Az-Zumar, ayah 41 of 75

إِنَّآ أَنزَلْنَا عَلَيْكَ ٱلْكِتَـٰبَ لِلنَّاسِ بِٱلْحَقِّ ۖ فَمَنِ ٱهْتَدَىٰ فَلِنَفْسِهِۦ ۖ وَمَن ضَلَّ فَإِنَّمَا يَضِلُّ عَلَيْهَا ۖ وَمَآ أَنتَ عَلَيْهِم بِوَكِيلٍ ۝٤١

39:41 Lo! We have revealed unto thee (Muhammad) the Scripture for mankind with truth. Then whosoever goeth right it is for his soul, and whosoever strayeth, strayeth only to its hurt. And thou art not a warder over them.