The Holy Prophet (pbuh&hp) said:

The Prophet (pbuh&hp) while returning from his last pilgrimage stopped the entire caravan at Ghadeer Khumm and made the announcement:

"Of whomever I am his master (mawla), Ali also is his master (mawla)."

References:

• al Hakim in Mustadrak ala al Sahihayn vol. iii, pp. 109110;
• Al Tirmidhi in his Sahih (Bulaq, 1292), ii, 298;
• Sunan Ibn Majah (Matba`at al Faruqi, Delhi), in "bab Fada'il ashab Rasul Allah (S)" from al Bara' ibn `Azib and Sa`d ibn Abi Waqqas;
• Al Hakim in Mustadrak (Hyderabad, 1313) from Zayd ibn Arqam (iii, 109, 533), Sa`d ibn Malik (iii, 116), from Rifa`ah ibn Ayas al Dabbi from his father from his grandfather (iii, 371), and from Buraydah al Aslami; (iii, 110; ii, 129);
• Imam Ahmad ibn Hanbal in his Musnad, al Matbaat al Maymaniyyah, Egypt, 1313, from al Bara' ibn Azib (iv, 281), Buraydah al Aslami (v, 347, 350, 358), Zayd ibn Arqam (iv, 372, iv, 368, v, 307), Ibn Abbas (i, 330), Abu al Tufayl (iv, 270) and Ali ibn Abi Talib (A) (i, 84, 88, 118, 139, 152, v, 307, 366, 419);
• Abu Nuaym al Isfahani; in Hilyat al Awliya (Egypt: Matbaat al­ Saadah, 1351) iv, 23, v, 26;
• Fakhr al Din al Razi; in al Tafsir al Kabir (Dar Tibaat al Amirah) under the verse 5:67;
• Al Khatib al Baghdadi, in Ta'rikh Baghdad (Matbaat al Saadah, 1360), vii, 377, viii, 290, xii, 343, xiv, 236;
• Al Nasai in Khasa'is (Matbaat al Taqaddum al Ilmiyyah, Egypt, 1348), pp.4, 21, 22, 23, 25, 26, 40;
• Al Muhibb al Tabari, in al Riyad al Nadirah (Matbaat al Ittihad, Egypt, 1st ed.), ii, 169, 170, 172, 203 and Dhakhair al Uqba (Egypt 1356), 86;
• Ibn Hajar al Asqalani in al Sawaiq al Muhriqah (al Matba`at al?Maymaniyyah, Egypt; 1312), pp. 25, 26;
• `Ali al Muttaqi al Hindi in Kanz al Ummal (Hyderabad, 1312), i, 48, vi, 83, 153, 154, 390, 397, 398, 399, 403,405, 406, 407;
• Ibn Hajar al Asqalani in al Isabah (Calcutta, 1853 A.D.), i, part one, 57, 319; iii, part one, 29; iv, part one, 14, 16, 61, 143, 169, 182; vi, 223, vii, part one, 78, 156;
• Ibn al Athir in Usd al Ghabah (al Matba`at al Wahbiyyah, Egypt, 1285), i, 308, 367, 368, ii, 307, 233, iii, 92, 93, 321, 374, iv, 28, v, 205, 276, 383;
• Ibn Qutaybah in al Imamah wa al Siyasah (Matba`at al Futuh al-Adabiyyah, 1331), 93;
• Al Tahawi in Mushkil al Aathar (Hyderabad, 1333), ii, 307;
• Al Manawi in Fayd al Qadir (Egypt, 1356), vi, 218, 358 and Kunuz al?Haqa'iq (Istanbul, 1285), 92;
• Al Haythami Majma al Zawa'id (Egypt, 1352), vii, 17, ix 103, 104, 105, 106,107, 108, 119, 163, 164;
• `Ali ibn Sultan Muhammad al Qari in Mirqat al Mafatih (al Matba`at al?Maymaniyyah, Egypt, 1309), v, 568.

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