the hypocrites are apprehensive lest a surah should be sent down against them informing them about what is in their hearts. say go on deriding. allah will indeed bring out what you are apprehensive of.
يحذر المنافقون أن تنزل عليهم سورة تنبئهم بما في قلوبهم قل استهزئوا إن الله مخرج ما تحذرون