Musannaf Ibn Abi Shayba 33:1355

Husayn ibn Ali narrated to us, he said: Ibrahim ibn al-Rabi’ ibn Abi Rashid informed me, he said: My father was impressed by Khalaf ibn Hawshab. He said: I said to him, "O my father, you are indeed impressed by this man." He said: "O my son, he grew up upon a good way, and he did not cease to be upon it." He said: And he used to be called by the kunya Abu Marzuq. Rabi’ said to him: "Change it." He said: So Khalaf said: "Then give me a kunya." He said: "You are Abu Abd al-Rahman."