It is narrated from Hazrat Jabir (may Allah be pleased with him) that once the Prophet (peace and blessings be upon him) led us in prayer in Madinah Munawwarah on the tenth of Dhul-Hijjah. Some people had already performed the sacrifice, thinking that perhaps the Prophet (peace and blessings be upon him) had already offered his sacrifice. When the Prophet (peace and blessings be upon him) came to know of this, he ordered that whoever had performed the sacrifice earlier should offer the sacrifice again, and that no one should perform the sacrifice before the Prophet (peace and blessings be upon him) has done so.