Muwatta Malik #1716

Yahya related to me from Malik from Abu'z-Zinad from Sulayman ibn Yasar that a slave was set free by one of the people on hajj and his master had abandoned the right to inherit from him. The ex-slave then killed a man from the Banu A'idh tribe. An A'idhi, the father of the slain man came to Umar ibn al-Khattab seeking the blood-money of his son. Umar said, "He has no blood-money." The A'idhi said, "What would you think if it had been my son who killed him?" Umar said, "Then you would pay his blood-money." He said, "He is then like the black and white Arqam snake. If it is left, it devours and if it is killed, it takes revenge."