Sa'id bin Masrooq Ath-Thawri سعيد بن مسروق الثوري · Funerals (Kitab Al-Jana'iz)

One of the oaths which the Messenger of Allah (ﷺ) received from us about the virtue was that we would not disobey him in it (virtue): that we would not scratch the face, nor wail, nor tear the front of the garments nor dishevel the hair.