Musnad Abu Ya'la al-Mawsili 173:1

Ya'qub ibn Ibrahim al-Nakari narrated to us, 'Uthman ibn 'Umar narrated to us, Harb ibn Surayj narrated to us, he said: A man from Banu al-'Adawiyyah narrated to me, he said: My grandfather narrated to me, he said: I set out to Medina and stayed at the valley. There were two men between whom was a single goat, and the buyer was saying to the seller, "Make my transaction easy." I said to myself, "Is this the Hashimite who has led the people astray? Is it him?" I looked, and he was a man of good physique, with a large forehead, a thin nose, and thin eyebrows. From the hollow of his throat to his navel was like a black thread of black hair, and he was between two garments. He approached us and said, "Peace be upon you," and they returned it to him. I did not wait long before the buyer called out, "O Messenger of Allah, tell him to make my transaction easy." He extended his hand and said, "Your wealth you possess. I hope to meet Allah, the Mighty and Majestic, on the Day of Resurrection, and that none of you will seek from me anything for which I have wronged him in wealth, blood, or honor, except by his right. May Allah have mercy on a person who is easy in selling, easy in buying, easy in taking, easy in giving, easy in paying, and easy in demanding payment." Then he went on. I said, "By Allah, I will certainly follow this man, for he has good speech." I followed him and said, "O Muhammad." He turned to me with his whole body and said, "What do you want?" I said, "Are you the one who led the people astray, ruined them, and turned them away from what their fathers used to worship?" He said, "That is Allah." I said, "What do you call to?" He said, "I call the servants of Allah to Allah." I said, "What do you say?" He said, "I bear witness that there is no god but Allah, and that I am the Messenger of Allah; that you believe in what Allah has revealed to me, disbelieve in al-Lat and al-'Uzza, establish prayer, and give Zakat." I said, "And what is Zakat?" He said, "That our rich return to our poor." I said, "What an excellent thing you call to." He said: There was no one on earth breathing who was more hateful to me than him, but he did not depart until he was more beloved to me than my child, my parent, and all people. He said, "I have known." I said, "I have known." He said, "Yes." I said, "I bear witness that there is no god but Allah, and that I am the Messenger of Allah, and that you believe in what has been revealed to me." I said, "Yes, O Messenger of Allah. I frequent a water source where there are many people, and I will call them to what you have called me to, for I hope they will follow you." He said, "Yes, call them." So the people of that water source—their men and their women—accepted Islam, and the Messenger of Allah, peace and blessings of Allah be upon him, wiped his head.