Musnad Ahmad 1371

It was narrated that ‘Ali (رضي الله عنه) said: The Messenger of Allah (ﷺ) gathered - or the Messenger of Allah (ﷺ) called - Banu ‘Abdul-Muttalib, among whom were some people all of whom liked to eat lamb and drink large amounts of water. He made a mudd of food for them, and they ate until they were full. And the food remained as it was, as if it had not been touched. Then he called for a vessel, and they drank until their thirst was quenched, and the drink remained as it was, as if it had not been drunk from. Then he said: "O Banu "Abdul-Muttalib, I have been sent to you in particular and to all the people in general. You have seen this sign. Which of you will swear allegiance to me, pledging to be my brother and companion?” Not one of them stood up for him, but I [‘Ali] stood up, and I was the youngest of the people. He said: "Sit down.” He said that three times, and each time I stood up for him and he said to me, "Sit down." Then the third time he put his hand on mine.