Musnad Abu Ya'la al-Mawsili 4:16

Al-Qawariri narrated to us, Yazid bin Zuray' narrated to us, Muhammad bin Ishaq narrated to us, Salim Abu al-Nadr narrated to us, from an elder from Banu Tamim who said: He sat with me while I was in the mosque of Basra during the time of al-Hajjaj bin Yusuf, and in his hand was his staff and a document he was carrying. He said, "O servant of Allah, do you see this book being of benefit to me with this companion of yours?" I said, "And what is this book?" He said, "A book that the Messenger of Allah, may Allah bless him and grant him peace, wrote for us." I said, "And how did he write it for you?" He said, "I came to Medina with my father while I was a young boy, with camels we had brought to Medina to sell. Talha bin Ubayd Allah was a friend of my father, so we stayed with him. My father said, 'O Abu Muhammad, go out with us and sell our mounts for us, for we have no knowledge of this market.' He said, 'As for me selling for you, I will not, for the Messenger of Allah, may Allah bless him and grant him peace, forbade that a resident should sell for a bedouin. But I will go out with you to the market, and when I am satisfied with a man for you from those who will trade with you, I will command you to sell to him.'" He said, "So we went out, and he went out with us. He sat in a corner of the market, and we bargained with men over our mounts until, when a man gave us what satisfied us, we came to him and asked his counsel regarding selling to him. He said, 'Yes, sell to him, for I am satisfied with his fulfillment and his reliability for you.' So we sold to him and took what was ours." He said, "My father said to him, 'Get us a document from the Messenger of Allah, may Allah bless him and grant him peace, that no injustice be done to us regarding our alms (sadaqat).' He said, 'That is for every Muslim.' We said, 'Even if [it is so]?' He said, 'So he walked with us and said, "O Messenger of Allah, these two would like for you to write for them that no injustice be done to them regarding their alms." He said, "That is for every Muslim." He said, "O Messenger of Allah, they would like to have a document from you." He said, 'So he wrote this document for them. Do you see it being of benefit to me with this companion of yours? For by Allah, he has committed injustice against us regarding our alms.' I said, 'I do not think so, by Allah.'"