Jami` at-Tirmidhi Book 43, Hadith 52
that he heard Mu'awiyah giving a Khutbah in Al-Madinah, and saying: "Where are your scholars, O people of Al-Madinah? I heard the Messenger of Allah (ﷺ) forbidding from these locks (of hair), and saying: 'The Children of Isra'il were only ruined when their women used them.'"