Mu'awiyya bin Jahma bin al-'Abbas · Chapters on Sacrifices

“Whoever among you sees the new crescent of Dhul-Hijjah and wants to offer a sacrifice, let him not take anything from his hair or nails.”

It was narrated from Anas bin Malik that a man slaughtered on the Day of Sacrifice, (meaning) before the ‘Eid prayer, and the Prophet (ﷺ) ordered him to do it again.