What the event is
In 10 AH the Prophet Muhammad performed his only farewell pilgrimage. On the return journey, at a place called Khumm where several roads met, he halted the caravan and addressed the assembled pilgrims. Before them he took the hand of Ali ibn Abi Talib and spoke the sentence both traditions record: 'Whoever I am his mawla, this Ali is his mawla.'
What is not disputed. The halt, the gathering, the raising of Ali's hand and that sentence as a report are found in Shia and Sunni sources, transmitted from companions including Zayd b. Arqam and Abu al-Tufayl.
What is disputed. The meaning of mawla in that sentence, and whether the occasion constitutes an appointment to leadership. Twelver Shia scholarship reads it as authority in the sense of Quran 33:6 and treats it as the public designation of Ali. Sunni scholarship predominantly reads it as friendship, support or closeness, and rejects the inference of appointment. Some Sunni scholars affirm the report while rejecting the Shia conclusion. Both readings are set out below with their reasoning.
What this page is. An evidence map, not a verdict. The interpretation is labelled as interpretation wherever it appears.