´It was narrated that Abu Hurairah said:` "Muhammad (ﷺ) said: 'Does the one who raises his head before the Imam not fear that Allah may turn his head into the head of a donkey?"'
Hadith ReferenceSunan an-Nasa'i / The Book of Leading the Prayer (Al-Imamah) / Hadith: 829
Hadith Gradingالألبانی:صحيح | زبیر علی زئی:صحيح مسلم