Hadith.2579 - In a narration from Hariz: "When the Messenger of Allah (swt) (peace be upon him and his family) entered the state of Ihram, Archangel Jibril (as) came to him and said: 'Command your companions to perform al-'ajj and al-thajj. Al-'ajj is raising the voice with the Talbiyah, and al-thajj is the slaughtering of sacrificial camels.'"