"Isn't he who raises his head before the Imām afraid that Allah may transform his head into that of a donkey or his shape into that of a donkey?"[Al-Bukhari]

عن أبي هريرة -- مرفوعاً: «أما يخشى الذي يرفع رأسه قبل الإمام أن يُحَوِّلَ الله رأسه رأس حمار، أو يجعل صورته صُورة حمار؟». (البخاري)