﴿ إِنَّهُمْ إِن يَظْهَرُوا۟ عَلَيْكُمْ يَرْجُمُوكُمْ أَوْ يُعِيدُوكُمْ فِى مِلَّتِهِمْ وَلَن تُفْلِحُوٓا۟ إِذًا أَبَدًۭا ﴾

“for, behold, if they should come to know of you, they might stone you to death or force you back to their faith-in which case you would never attain to any good!"”

(For they, if they) the Magians (should come to know of you, will stone you) kill you (or turn you back to their religion) Zoroastrianism; (then ye will never prosper) you will never escape from Allah's punishment.