AL KAHFI — Ayat 20

إِنَّهُمْ إِن يَظْهَرُوا عَلَيْكُمْ يَرْجُمُوكُمْ أَوْ يُعِيدُوكُمْ فِي مِلَّتِهِمْ وَلَن تُفْلِحُوا إِذًا أَبَدًا

Indeed, if they come to know of you, they will stone you or return you to their religion. And never would you succeed, then - ever."