Musannaf Ibn Abi Shaybah 34654 — The virtue of the Arabs

Muhammad bin Abdullah bin Kathir bin al-Salt (may Allah have mercy on him) said: A freed slave of ours married an Arab woman. So he was brought to Umar bin Abd al-Aziz (may Allah have mercy on him) and help was sought against him. He (may Allah have mercy on him) said: "By Allah! The freed slave of the family of Kathir has certainly gone beyond his rank and his limit."