Qur'an 13:37

وَكَذَٰلِكَ أَنزَلْنَـٰهُ حُكْمًا عَرَبِيًّا ۚ وَلَئِنِ ٱتَّبَعْتَ أَهْوَآءَهُم بَعْدَ مَا جَآءَكَ مِنَ ٱلْعِلْمِ مَا لَكَ مِنَ ٱللَّهِ مِن وَلِىٍّ وَلَا وَاقٍ

Thus have We revealed it, a decisive utterance in Arabic; and if thou shouldst follow their desires after that which hath come unto thee of knowledge, then truly wouldst thou have from Allah no protecting friend nor defender.