Hadith No: 3
Al-Ajuri - al-Shari'ah - al-Kitab al-Jami' Fada'il Ahl al-Bayt (peace be upon them)
Chapter on the Prophet's (peace be upon him and his holy progeny) instruction to his Ummah to hold fast to the Book of Allah, the Mighty and Majestic, and to the Sunnah of His Messenger (peace be upon him and his holy progeny), to love the People of his House, and to adhere to what they are upon in truth, as well as the prohibition against falling behind their beautiful, good way.
Volume: (5) - Page Number: (2221)
[The text is lengthy, so only the relevant excerpt is provided here]
1706 - Abu Bakr ibn Abi Dawud narrated to us, who said: My uncle Muhammad ibn al-Ash'ath narrated to me, who said: Zayd ibn Awf narrated to us, who said: Abu 'Awaneq narrated to us from al-A'mash, who said: Habib ibn Abi Thabit narrated to us from Amr ibn Wathila from Zayd ibn Arqam, who said: When the Messenger of Allah (peace be upon him and his holy progeny) returned from the Farewell Pilgrimage and descended at Ghadir Khumm, he commanded that some trees be gathered and then stood up and said: "It seems that I have been invited and I have responded,
and I have left among you two precious things, one of them is the Book of Allah, the Mighty and Majestic, and my family, the People of my House. See how you will fare in your treatment of them, for they will not be separated until they come to me at the Pond." Then he said: "Indeed, Allah, the Mighty and Majestic, is my Mawla, and I am the Mawla of every believer," and he took Ali ibn Abi Talib's (peace be upon him) hand and said: "Whoever I am their mawla, this Ali is their mawla. O Allah, befriend whoever befriends him and be an enemy to whoever opposes him...."