Musannaf Ibn Abi Shayba 13:3047

Abu Bakr narrated to us, he said: Ubayd Allah ibn Musa narrated to us, he said: Sufyan narrated to us, from Uqbah ibn Abi al-Ayzar, who said: I came to al-Sha'bi with a man against whom I had a claim, but I did not have any evidence against him. He said: "Take a guarantor for me from him." But he (the man) refused to take a guarantor for me from him.