Musannaf Ibn Abi Shayba 13:2405

Abu Bakr narrated to us, he said: Waki’ narrated to us, he said: Musa ibn ‘Ubaydah narrated to us, from ‘Abdullah ibn Dinar, that a man was fertilizing his land with human excrement. ‘Umar ibn al-Khattab said to him: "Are you the one who feeds the people what comes out of them?"